anatomy & physiology - basic human anatomy and physiology€¦ · anatomy!&!physiology!!...

Anatomy & Physiology

of 94 ©Universal Light Group 2020 used with permission by SMCPLT™

©Universal Light Group 2020 used with permission by SMCPLT™

Authors: 1. L Ford 2. J Mittiga

All rights reserved. Materials may not be reproduced in whole or in part without written permission from the authors. This includes the right to reproduce, photocopy, store in a retrieval system or be transmitted by any means electronic, mechanical, or technological whatsoever without expressed written permission from the authors. All images are owned by SMCPLT unless otherwise noted.



Introduction

Anatomy is the scientific study of the body’s structure from the gross (large) structures that can be seen by the naked eye to the microscopic (very tiny) structures only seen with a microscope.

Physiology is the study of the chemistry and physics (function) of the body structures and how they work together to maintain homeostasis, steady internal conditions.

This course presents a basic understanding of the anatomy and physiology of the human body. While in no way a comprehensive presentation of the topic, it is intended to introduce the basics in an easily digestible way.

Consider your study of this material a 10 course meal. You are is invited to take a small bite (one chapter at a time) and chew on each concept while imaging how that structure (anatomy) functions (physiology) in your body.

The examination questions at the end of each chapter are to be used as in an open book fashion. Answers and feedback are provided.

Most students taking this course are exploring a natural therapy healing modality. Key to understanding how your modality impacts the healing processes of the body is your understanding of how the body achieves and maintains homeostasis.

The body is a miraculous vehicle (hardware) with built-‐in self-‐healing software. Is that software energetic? Is it physiologic? Is it Divine? Does it reside in the brain? In the nucleus? In the mitochondria? In the 8th chakra? These questions are beyond the scope of this course and yours to ponder.

Enjoy!

Lana J Ford PhD FAOTA Jody Mittiga DNM ANP The Universal Light Group SMCPLT Certified Instructors



INDEX Introduction 3

CHAPTER 1 The Skeletal System 5 Skeletal System Exam 17

CHAPTER 2 The Muscle System 19 Muscle System Exam 25

CHAPTER 3 The Integumentary System 27 Integumentary System Exam 33

CHAPTER 4 The Respiratory System 35 Respiratory System Exam 39

CHAPTER 5 The Circulatory System 41 Circulatory System Exam 46

CHAPTER 6 The Lymphatic System 48 Lymphatic System Exam 52

CHAPTER 7 The Digestive System 53 Digestive System Exam 59

CHAPTER 8

The Urinary System 61 Urinary System Exam 64

CHAPTER 9 The Endocrine System 65 Endocrine System Exam 74

CHAPTER 10 The Nervous System 76 Nervous System Exam 91



Chapter 1: The Skeletal System To begin the study of the human body we start with the structure that shapes the container – the skeletal system. The skeleton forms the framework for the human body. It is composed of individual bones characterized by their shape. These bones articulate (move) with each other at joints.

While it is not necessary to remember all 206 bones, you will find many similar names throughout the entire anatomy course. For example, the femur bone in the leg has a femoral artery and femoral nerve supply; the radius and ulnar bones correspond to the radial and ulnar arteries and nerves.

The structure and function of long and flat bones is explored in greater detail to demonstrate the interrelationship between the skeletal structure and other body systems particularly the digestive system, central nervous system, and autonomic nervous system.

Learning Objectives

} Describe the function of the skeleton

} Be familiar with the types of bones as this will help understand how they come together and form joints

} Identify where red blood cells are formed

} Explain how osteoblasts and osteoclasts are different and how they are related to weight bearing and skeletal remodeling

} Identify major parts of the axial skeleton and appendicular systems

} Describe cartilage and its role in the system

} Locate different sections of the spinal column

} Describe function of cerebral spinal fluid



Functions of the Skeleton

There are five general functions of the skeleton. Providing:

1. support for the entire body 2. protection of vital organs 3. storage of various minerals 4. motion through joints and attached skeletal muscles 5. the formation of blood cells through a process called hematopoiesis

Support for the body: Posture

Posture is an important and over-‐looked component of health. It is one of the primary purposes of the skeletal system as it is responsible for maintaining form. “Good posture” allows adequate room for the organs to function properly. Structural alignment contributes to nerve conduction, blood flow and lymphatic drainage. Chronically poor posture exerts forces that result in remodeling the shape of the skeleton. Posture is also important for maintaining muscular balance allowing muscles to function effectively. Skeletal misalignment often results in pain.

Types of Bones

Individual bones are categorized into 6 major groups: long, flat, short, irregular, pneumatic, sesamoid.

} Long bones

The large bones of the upper extremity are the humerus in the upper arm, the radius and ulnar in the lower arm, and the phalanges in the hands and feet. The clavicle, known as the collar bone, is not illustrated.

} Flat Bones

Flat bones are typically very thin bones making them particularly susceptible to traumatic fracture. These bones include the cranial bones of the head and face, the “wing bone” on the backside of the body called the scapula, the sternum or breastbone, rib bones and the pelvic or hip bone (not shown).

Source: www.visiblebody.com




} Short Bones

Shorts bones vary in shape depending on their location in the body. There is very little cushion around these bones as they tend to create small sliding motions rather than move large bony parts. Included in this type are the tarsal bones of the feet, carpal bones of the hands and the patella of the knee.

} Irregular bones

Irregular bones vary in size and the number of articulating surfaces particularly the vertebrae of the spine. The sacrum bone is also in this category.

} Pneumatic Bones

Pneumatic bones are typically found in the skull and sinuses. Unlike other bones, its air spaces are filed with mucous membranes. The sinuses serve as a resonance chamber for the production of speech (no image).

} Sesamoid bones

There are only two sesamoid bones in the body, located in the knee joint. Their primary purpose is to keep the muscle away from the joint thereby increasing leverage in muscle contraction.

Bone Composition

When people think of bones they usually think of the dried specimens seen in school libraries and museums. Bone in a live human, living bone, is much more pliable and quite vascular. Living bone is in a constant state of self-‐repair containing cells that lay down new bone. It also contain blood vessels and nerves that contribute to self-‐repair and remodeling.

Remodeling changes the shape and density of living bones to meet the changing demands of life. Exercise keeps living bones strong and pliable. Immobility weakens the bone matrix. That is why astronauts who spend many hours in zero gravity must regularly perform exercises to keep their bones







strong. And adults who routinely exercise as they age tend to maintain their structural integrity which contributes to functional independence.

Bones are composed of minerals, mostly calcium, embedded on a protein matrix called collagen. Calcium is the mineral that keeps living bones strong. Calcium is a vital nutrient necessary for muscles contraction (including the heart) and nerves function (including nerves in the brain). Calcium is also an important factor in blood clotting. Calcium, therefore, is an essential micronutrient for homeostasis. Ninety-‐nine percent of the calcium in the body is stored in the bones and teeth.

it is important for young people to get sufficient calcium in their diets and for everyone as they age to maintain an adequate intake. When there is sufficient calcium in the diet, our bodies store calcium in the bones making/keeping them strong. Bones are often thought of as a “calcium bank”.

In order to maintain life, the pH (acid/alkaline balance) of the blood must be kept constant (neutral). The body uses calcium from the bones to maintain proper pH of the blood. When the pH of the blood begins to fall (become acidic), the body will pull calcium out of the bones into the blood stream to buffer the acidic condition. Stress (a function of the autonomic nervous system) causes systemic acidic conditions.

Calcium pulled from the bones is eventually lost through the urine. Excessive calcium loss leads to a weakening of the bones, a condition called osteoporosis. In addition to stress, excessive loss of calcium may also be due to the consumption of too many acid-‐producing foods common in today’s “modern” diet. Research suggests the biggest culprits for calcium loss are products containing refined sugar, enriched flour, and carbonated beverages.

The outer layer of bone called the periosteum is composed of compact bone tissue containing of two types of cells osteoblasts and osteoclasts. Osteoblasts are bone cells that lay down new bone while osteoclasts are bone cells that break down old bone. These cells are part of the body’s innate repair system. Spongy bone tissue found inside the bone is composed of thin rods arranged in an intricate matrix. Yellow marrow is found in the long spaces while red marrow is found in the ends of long bones in the extremities and rib joints, the flat bones of the skull and the sternum. Bone Changes

Specific structures called hydroxyapatite crystals are mineral deposits in the matrix of bone tissue giving bones their hardness and strength. When these crystals are compressed through movement a local electric current is created. This phenomenon is called the



piezoelectric effect. Bone tissue grows when subjected to the piezoelectric effect in weight bearing (resistance) exercise. Think about young children just learning to walk and how weight bearing contributes to development of their long bones. Since compression on the bone with weight bearing (resistance) exercise leads to bone growth and regrowth, it is important in bone fracture healing. Bones loose mass when not subjected to these forces as is the case of people living a sedentary lifestyles, especially the elderly who become functionally immobile for one reason or another. Keep in mind the building up and tearing down of bone tissue through changes in osteoblast and osteoclast activity is responsible for the remodeling of the skeleton throughout life.

Major Parts Human Skeletal System

Source: www.alison.com

Axial Skeleton

} The skull } Thoracic cage (rib cage) } Vertebral column (spine)

Appendicular Skeleton

} Bones of the upper and lower limbs

} Pectoral & Pelvic Girdles



Axial Skeleton The cranium is the spherical container that protects the brain. Blood vessels and nerves enter and leave the cranial cavity through openings at the base of the skull. Notice that the names of bones correspond to brain structures with the frontal bone protecting the frontal lobe.

The facial skeleton is attached to the anterior (front) and inferior (bottom) of the cranium. It provides the passage of air through the nose and food into the mouth linking the skeletal system to the respiratory and digestive systems.

The rib cage is made up of sternum (breastbone), the thoracic vertebra and 12 pairs of ribs attached posteriorly to the vertebrae and anteriorly to the costal cartilages. The function of the rib cage is to enable motion of the thoracic region of the

spine and to allow movement of the ribs and cartilage imposed by movement of the diaphragm during breathing. The rib cage further provides protection for the lungs, heart and liver. The vertebral column is a series of individual segments called vertebrae placed on top of each other with a cartilage cushion or disc between. Specific sections include the cervical, thoracic, lumbar spine along with the non-‐segmented sacrum and coccyx.



The two upper two vertebrae are specifically designed for head motions. Articulation between the occipital base of the skull and the 1st cervical vertebra (atlas) allows for anterior-‐posterior (front-‐back) motions of the head. Articulation between the 1st vertebra (atlas) and 2nd vertebra (axis) allows for rotary, tilting or turning motions of the head.

Weight bearing in the axial skeleton is largely mediated through the lumbar and sacral vertebrae. Natural curvatures function as shock absorbers for surrounding structures. Intervertebral discs act as shock absorbers and allow for spinal flexibility.

Similar to bone changes, lack of exercise and the loss of essential trace minerals due to stress and dietary habits cause disks to become more brittle and less flexible over time.

Appendicular Skeleton The appendicular skeletal system is composed of long and short bones found in the legs and arms. These bones are united in the body at critical intersections called “girdles”. The pectoral girdle joins the sternum and the clavicle in the upper body at the shoulders and includes the well-‐known rotator cuff

The pelvic girdle is attached to the sacrum with ligaments. The pelvic girdle on the both sides of the sacrum form a solid structure known as the body pelvis. The pelvis forms the large structure for the hip joints

Source: www.alyvea.com



and the pubic symphysis which expands during childbirth in women. The obturator foramen (opening) gives passageway for the sciatic nerve. Impingement of this opening often a source of hip and leg pain.

Structure and Function of Long Bones

Long bones have two main parts: the diaphysis and the epiphysis. The periosteum is a dense fiber covering the outer surface of the bone containing the osteoblasts for bone formation. The periosteum also contains veins, arteries and lymphatics bundled together into a structure called the neurovascular bundle which nourishes the bone. The epiphysis at the ends of the long bones is covered by a cartilage made up of hyaline tissue that functions to make movement easier.

Bone marrow is a spongy bone containing progenitor cells that are the source of hematopoietic and mesenchymal stem cells.

The hollow of the diaphysis, the medullary cavity, is filled with yellow marrow -‐a gelatin-‐like tissue that contains

mesenchymal cells. Mesenchymal cells are stem cells that can differentiate into osteoblasts (bone cells), chondrocytes (cartilage cells), myocytes (muscle cells), and adipocytes (fat cells). It is involved in the storage of fats which helps maintain bone homeostasis. Red bone marrow is a delicate, highly

vascular fibrous tissue that contains hematopoietic stem cells which are the source of all blood cells (red, white, platelets) producing more than 200 billion new blood cells every day.

It’s easy to see the interrelationship between the skeletal system and the cardiovascular system since long bones are the genesis of the blood filling the vessels of the cardiovascular system.

Source: openstax.org

Source: medicalnewstoday.com



Development of Long Bones

Long bone development begins in the fetus as hyaline cartilage. This cartilage is responsible for the lengthening of bone structures as it is replaced by bone cells in the shaft of the bone. Shortly after birth secondary centers of ossification develop at the ends of bones.

By puberty bone development takes over the work of the birth cartilage. Most growth in bone length occurs during and shortly after puberty. After puberty bones tend to grow in width rather than length. Throughout the remainder of life there is a constant tearing down (osteoclastic activity) and rebuilding (osteoblastic activity) and remodeling the bony structure of the body.

Structure of Flat Bones

The cranium, scapula, sternum, rib and hip bones are considered flat bones. Bone growth occurs at the edges as there is no bone shaft. Flat bones resemble a sandwich with a layer of cancellous bone between two bony tables.

Unique Characteristics of Flat Bones

Adjacent to nasal cavities are many flat bones hollowed to form paranasal sinuses which takes the place of

cancellous bony tissue. These boney structures are lined with skin tissue called mucous membranes which are the source of histamine responses leading to the classic runny nose.

Development of the mastoid bone is formed by the extension of the air-‐filled cavity of the middle ear, often a site for ear infections.

Bones of the skull are curved and form a sphere for protection of the brain. The flat bones in young children are not fully developed meaning they remain quite flexible. In adults the bones become fully formed and are often fused along suture lines. Mild direct blunt force trauma causing cracks or fractures in the cranium will usually heal by activity of the osteoblasts at the margins



of the defect. Such injuries, however, causes the soft tissue of the brain to be bounced against the cranium resulting in brain tissue trauma at the site of impact and in heterogeneous locations throughout the brain.

Fluids of the Skeletal System

The cerebral spinal fluid (CSF) (shown in blue) is a clear, colorless fluid found in the brain and spinal column. CSF is produced in the ventricles of the brain (1) and flows from the brain to the tailbone tip of the spinal cord. It acts as a cushion and buffer for the central nervous system by providing mechanical and immunological protection. The CSF also serves a vital function in auto regulation of cerebral blood flow (CBF).



Joints of the Skeletal System While the medical classification term are important, it is most helpful to have a general idea of how muscles move bones at points of articulation called joints. Observing how your own body moves may be your best resource.

Joints are characterized in 3 different way.

} By the material holding the joint together and the relative mobility

The points of articulation between bones that are fused together is called a synostosis joint (found in the sutures of the cranial bones). Where bones are held together by cartilage it is called a synchondrosis joint (found in the femur connection to tibia and fibula in the knee). Bones held together by a connective fibrous tissue it is called a syndesmosis joint as in where the radius and ulna meet at the elbow. While cartilage is beneficial to specific joints it does not often regenerate or replicate itself when damaged often resulting in pain frequently in the knee and hip joints. Connective tissue, on the other hand, can undergo repair or replacement which may be augmented by non-‐surgical intervention.

} By relative mobility The synostosis joint of the cranial bones are non-‐mobile. Semi-‐mobile syndesmosis joints are connected through connective tissue (elbow). Synchondrosis joint structures that facilitate mobility are synovial articulations (knee, shoulder, hips) and usually have a tough membrane filled with a synovial fluid.

} By degrees of freedom referring to the number of planes in which movement is permitted

One degree of freedom means the joint in uniaxial. Uniaxial joints move in one direction only. Hinge joints are found in the elbow, knee and small bones of the fingers and toes.

Two degrees of freedom means the joint is biaxial. Biaxial joints move in two directions. An example would be the wrist and ankle joints which move back and forth and side to side.



With three degrees of freedom, we say the joint is multi-‐axial. Not only does it move up and down and sideways, it rotates within its own socket. The shoulder and hip are examples of ball and socket joints.

Teeth Teeth are considered a functional part of the digestive system and because they are composed of bone and the minerals of calcium and phosphorus they are part of the skeletal system. Structure of Teeth Enamel is the hard bone coating over the dentin. The pulp contains the nerve and blood supply to the teeth. Teeth are held in place by soft gum tissue, which when inflamed, creates a condition known as gingivitis.

Adults humans typically have 12 molars, 8 premolars, 4 canines and 8 incisors. Molars are designed for chewing while incisors and canines are for biting and tearing. This is an important distinction to remember as it links the teeth to both the digestive system processes and the autonomic nervous system.

To further illustrate the inner-‐connectivity between body systems, each tooth is energetically connected to a gland and an individual organ through the Chinese meridian system.



This concludes Chapter 1: The Skeletal System. Answer the following questions before proceeding to the next chapter.



Exam: Skeletal System

Check one or more correct answers 1. What is the function of the Skeletal System? ___a. support for the entire body ___b. protection of some vital organs ___c. storage of various minerals ___d. motion through joints and attached skeletal muscles ___e. hematopoiesis – formation of blood cells 2. Why is posture important? ___a. contributes to red blood cell formation ___b. allows room for organs to function ___c. maintains muscle balance ___d. contributes to blood flow and lymphatic drainage

3. Red blood cells are formed ___a. in the shaft of the long bones ___b. at the ends of the bones ___c. in the sternum ___d. in the skull ___e. in the rib joints 4. What are the major parts of the axial skeleton? ___a. skull ___b. rib cage ___c. pelvic girdle ___d. vertebral column

5. What are the parts of the vertebral column? ___a. cervical ___b. sternum ___c. thoracic ___d. lumbar ___e. skull 6. Uniaxial or hinge joints that move ONLY in one direction include: ___a. shoulder joint ___b. elbow joint ___c. finger (phalanx) joints ___d. hip joint ___e. ankle joint



7. A biaxial joint that moves back and forth and side to side is found in the ___a. wrist ___b. elbow ___c. shoulder ___d. neck 8. Ball and socket joints (that move in multiple directions) are found in the ___a. feet ___b. spine ___c. shoulder ___d. hip

9. Piezoelectric effect ___a. occurs when hydroxyapatite crystals in bone tissue are compressed ___b. is prominent during weight bearing activities (walking) ___c. when combined with activity of osteoclasts and osteoblasts remodels skeletal structure ___d. stimulates the production of red blood cells 10. Cerebral Spinal Fluid ___a. is a fluid carrying hemoglobin in the blood ___b. provides immune protection for the brain ___c. is a fluid circulating inside the skull ___d. assists with blood flow in the brain



Chapter 2: The Muscular System The muscular system is often called the musculoskeletal system because of the intimate relationship between these two structural systems – the muscles and the skeleton. Muscles hold bones in place and facilitate the movement of the entire body.

Learning Objectives

} Describe the functions of muscle tissue } Understand the properties of muscle tissue } Identify three types of muscle fibers } Associate types of movement according to joint type

Muscles of the Human Body

Source: www.slideshare.net



Function of Muscle Tissue The function of muscle is to facilitate movement of the body at large and within the body. Muscles let the body walk, run, tilt and turn the head, and manipulate objects with hands, arms, fingers and toes. Muscles stabilize body posture in standing and sitting. Small muscle movement regulates organ volume. For example, gastrointestinal muscles move food through the digestive system. Movement of the diaphragm regulates the intake and expulsion of air in the lungs. Cardiac muscles pump the heart. Other muscles act to move materials and fluids within the body. Additionally, muscle movements produce heat during contraction to maintain body temperature. Properties of Muscle Tissue

} Electrical excitability Muscles respond to stimuli by producing electrical signals which sends as action potential along a cell membrane. Electrical signals are the result of chemical stimuli from messenger molecules called neurotransmitters.

} Contractibility Muscles contract or shorten when stimulated by an action potential creating one of two types of movement: isotonic or isometric. In isotonic contractions the tension remains constant as muscle

shortens and produces movement. An example would be the repeated lifting of the weight through movement of the elbow. In an isometric contraction the muscle has tension but does not shorten thus no movement is produced. An example would be holding a heavy object with the elbow straight. } Extensibility Extensibility refers to the ability of muscle to stretch without being damaged. Think about stomach smooth muscles. When

the stomach is full of food it expands. Cardiac muscles function similarly when the heart chambers fill with blood. Skeletal muscles exhibit extensibility during intentional stretching during exercise.

} Elasticity Elasticity refers to the ability of a muscle to return to its original length and shape after contraction or extension. Think again of the stomach muscle returning to normal size when empty.



How Muscles Move

All muscle tissue movement is fueled by ATP (adenosine triphosphate) inside the cell. ATP triggers the two proteins responsible for muscle movement: myosin and actin. Myosin converts chemical ATP energy into mechanical energy. The myosin head (shaped like a double headed golf club) sends a signal to a binding protein called actin. Actin in turn forms a filament that twists into a helix to push or pull the muscle fiber.

In a relaxed state myosin is blocked from actin by two regulatory proteins called troponin and tropomyosin.

Types of Muscle Tissue

There are three types of muscle tissue: skeletal, smooth, and cardiac. All are composed of striated fast (white) and slow (red) fibers. Skeletal muscles are bundles or columns of fibers allowing for action even if one bundle is damaged allowing muscle to function in a weakened state. Smooth muscles are elongated structures found in the walls of the visceral organs and blood vessels. If there is damage to a single fiber the surrounding fibers generally take over function. Cardiac muscles have a branched structure and are found only in the heart. Damage to a single fiber may result in irregularity of muscle contraction.

} Structure and function of skeletal muscles

The primary function of skeletal muscles is to move the bones of the skeleton. Individual muscle fibers are encased or bundled in a sheath of connective tissue. There is usually one artery, one or two veins, and a motor neuron for each muscle bundle. At the ends of the muscles the connective tissue forms a dense tendon attachment to the bone. Understanding this relationship makes it easy to recognize that tears in the tendon may results in poor or improper muscle function.

Skeletal muscles contract voluntarily to produce movement of limbs. Other muscles contract involuntarily as in movement of the diaphragm in breathing.



} Structure and function of smooth muscles

Smooth muscles are characterized by small spindle shaped fibers nestled together. They are located in the hollow structures of blood vessels, the stomach, intestines, gall bladder, and urinary tract. Their function is to move fluids and eliminate wastes through involuntary movement.

} Structure and function of cardiac muscles

Cardiac muscles are specific to the heart. They are composed of striated long and slow acting fibers that attach to each other end to end. They have a branched structure with only one central nucleus. These fibers form the heart wall and their movement is involuntary.

Classification According to Action

Movement is the result of muscle groups working together assuming the skeletal structure is intact. Skeletal muscles are arranged in opposite pairs and perform movement to shorten or lengthen thus allowing movement of the bony segment. When a muscle shortens or contracts it is called the agonist. When a muscle lengthens it is called the antagonist.

Skeletal muscles can be either agonists or antagonists. For example, the biceps acting as an agonist contracts to move the forearm toward the upper arm. At the same time the triceps acts as an antagonist to lengthen thereby allowing movement. The opposite is also true. When the triceps acts as the agonist to straighten the forearm the biceps acts as the antagonist to relax and allow movement. The relationship between the paired muscles is critical for coordinated movement.

Muscles called synergists aid the agonist but do not act as prime movers. An example would be the small muscles on either side of individual finger joints that stabilize the joint allowing the long muscle fibers that cross multiple joints to move the segmented parts.

Fixators stabilize the agonist so that it can work more effectively. For example, scapular muscles fix the scapula (shoulder wing like bone) while movement takes place through long muscles that move the shoulder and forearm.

Types of Movement

Skeletal muscles move as coordinated pairs. This may be best understood in the context of the types of movement they produce.



} Flexion/Extension

Flexion and extension occur in uniaxial or hinge joints of the fingers, elbow, knee and toes. Flexion means there is movement of the distal (farthest away) part toward the proximal (closest to center) part. Examples would include movement of the forearm toward the upper arm with motion occurring at the elbow. Extension refers to the straightening of the forearm; moving farther away from the bicep. These movements use both agonist and antagonist muscle groups.

} Eversion/Inversion

Eversion/inversion is a biaxial movement meaning the muscles move the joint in two directions. Examples are the wrist and ankle which move up and down as well as from side to side.

} Pronation/Supination

Pronation/supination is also a biaxial movement of the elbow. When the elbow is flexed with the forearm and palm facing upward the movement is called supination. When the forearm remains flexed and the forearm turns over, palm down, the movement is called pronation.

} Abduction/Adduction

Abduction/adduction is movement in relationship to the center of the body. Abduction is movement away from the center of the body. Adduction is movement toward the center of the body. These movements are typically found in multiaxial joints such as the shoulder and hip joints

} Horizontal Abduction/Adduction

Horizontal abduction/adduction is movement horizontally across the front of the body. Visualize moving your right arm across your chest to the left with movement of both the scapula and the humerus.

Control of the Muscular System

The muscular system is dependent on the brain for motor control. Signals sent from the brain’s motor cortex to the body direct the motion. Sensations coming from the body’s peripheral nervous system travel to the brain providing information about the environment and literally informing the next step.



Control the left side of the body takes place in the right side of brain and the right side of the body is controlled by the left brain.

The homunculus is an illustrated map of both sensory and motor control of the body represented in the cortex of the brain. Notice the face and hands have the greatest density of motor and sensory innervations.

This concludes Chapter 2: The Muscular System. Answer the following questions before proceeding to the next chapter.



Exam: Muscular System

Check one or more correct answers 1. Action potential refers to as: ___a. electrical signals passed along the cell membrane ___b. pumping action of the heart ___c. electrical signals from neurotransmitters 2. Movement of the left side of the body is from ___a. right side of the brain ___b. left side of the brain ___c. both sides of the brain 3. Which muscle fibers have involuntary control ___a. cardiac fibers ___b. smooth fibers ___c. skeletal fibers

4. Identify the properties of muscle tissue ___a. electrical excitability ___b. contractibility ___c. immobility ___d. elasticity 5. Muscles that occur in bundles with fast (white) and slow(red) moving fibers include: ___a. smooth fibers ___b. cardiac fibers ___c. skeletal fibers

6. Smooth muscles are located in the: ___a. blood vessels ___b. stomach ___c. intestines ___d. urinary tract ___e. face 7. Skeletal muscles have ___a. one artery one muscle bundle ___b. one or two veins per muscle bundle ___c. motor neurons for each muscle bundle



8. Isometric contraction means: ___a. tension, contraction, muscle shortening to creating movement ___b. no tension, muscle lengthens, allowing movement ___c. muscle has static tension, no movement 9. Identify the function of muscle tissue ___a. stabilize a body part ___b. produce body movement ___c. move fluids in the body 10. What chemical triggers proteins to produce muscle movement ___a. acetylcholine ___b. adenosine triphosphate (ATP) ___c. adrenaline



Chapter 3: Integumentary System The integumentary system (skin) is the largest organ in the human body. It encloses all of the internal structures and is the site of sensory receptors connecting the human with the external world.

Learning Objectives

} Identify the functions of the skin

} Describe the 3 main layers of the skin

} Identify what happens in these 3 layers

} Recognize the main structures of the nails and hair

} Identify types of sensations occurring in the skin

Functions of the Skin

} Protection

The skin provides a physical, chemical and biological barrier against the outside world. It is the first line of defense against microbes and harmful chemicals. Lipids or fatty substances excreted through the skin retard water evaporation preventing dehydration. Oily sebum secreted from the sebaceous glands protects hair and nails and it contains bactericidal chemicals that kill surface bacteria. The skin’s pigment called melanin provides protection from UV light.

} Excretion

Although nearly waterproof, the skin excretes 200-‐400 ml of water daily (depending on activity level). The skin also assists in removing heat through sweating. Sweating removes small amounts of salt and carbon dioxide.

} Absorption

The skin absorbs small amounts of mostly fat-‐soluble materials including Vitamin A, D, E, and K. It absorbs oxygen and carbon dioxide gases. Skin absorbs almost any substance applied to it including lotions, essential oils, and medications. Not all absorptions are healthy. And, because of this absorption quality, toxic substances can cause allergic reactions: poison ivy, detergents, makeup, and inorganic substances like nail polish remover.

} Thermoregulation

Thermoregulation is the regulation of body temperature. The sympathetic nervous system is responsible for monitoring body temperature and initiating appropriate skin and motor responses. Sweating, while an act of excretion,



serves to cool the surface of the skin as the sweat evaporates from the skin surface. Shivering is a muscle contraction activity intended to create heat. Extreme cold causes blood vessels in the skin to contract preventing passive heat loss and protecting internal organs. Below freezing temperatures can result in a condition called frostbite. The skin may also divert blood flow to underlying muscle tissue during exercise or in response to stressful situations.

} Synthesis of Vitamin D

Vitamin D3 (cholecalciferol) is synthesized from a cholesterol derivative found in the skin when skin is directly exposed to the UV wavelengths in sunlight. Enzymes in the kidney and liver modify the activated molecule producing calcitriol which aids absorption of calcium in foods from the gastrointestinal tract. Vitamin D is essential for immune system support.

} Cutaneous sensations

The skin is essentially a sense organ. Cutaneous sensations refer to sensory nerve receptors on the surface of the skin resulting in the sensations of touch, pressure, vibration, heat, cold, and tickling.

These cutaneous nerve receptors send stimuli to the central nervous system (brain and spinal cord) which activate skeletal muscles to respond to look at the fly that landed on your leg or withdraw from the hot pot your hand just touched. The persistent sensation of pain is usually an indication of actual tissue damage. The Homunculus illustration in the Muscular System Chapter suggests the highest number of receptors on the skin are found in the lips and fingers of the hand.

Structure of the Skin

} Epidermis

The outermost layer of the skin is called the epidermis. The epidermis is not well vascularized and is very thin comprised of mostly dead skin cells which flake off and are replaced constantly. It does contain a tough fibrous protein called keratin that protects the skin and underlying tissues from heat, microbes, and chemicals. Most of the remaining cells are melanocytes which contain the protein melanin that contributes to skin color.

} Dermis The secondary layer has more depth. It is highly vascular and contains collagen, elastic fibers, nerves, glands and hair follicles.

Burn blister



} Subcutaneous

The deepest layer of the skin contains fat deposits and nerve endings responding to deep pressure.

Layers of the Epidermis

The specific layers of the skin have special functions contribute to the primary function of the skin which is protection.

} Stratum Corneum The outermost layer of the epidermis called the stratum corneum. It is composed of 25-‐30 layers of dead skin cells. Between the cells are lipids or fat deposits which help make this layer water repellant. Cells in this layer are constantly replaced by cells from a deeper layer that migrate upward. Constant exposure to friction stimulates abnormal thickening called a callus.

} Stratum Lucidum The second layer of the epidermis called the stratum lucidum is present only on the fingertips, palms and soles. It contains layers of filaments and thickened plasma membranes.

} Stratum Granulosum The stratum granulosum is the middle layer between strata where new cells are formed and replace the dead cells in the top layer. It contains lamellar granules which fill the space between cells and acts as a sealant keeping water in and microbes out.

} Stratum Spinosum

Largest layer in the epidermis, called the stratum spinosum, contains many sided keratinocytes backed together. Their shape contributes to both strength and elasticity of the skin.

} Stratum Basale The stratum Basale is the deepest layer of the epidermis. It contains stem cells that continuously produce keratinocytes. These cells contain mitochondrion which generate the ATP (cell energy) needed for all cell function. This layer also contains the sensory neurons for temperature and pain.



Layers of the Dermis The second layer of the skin is called the dermis. It contains blood vessels, nerves, glands and hair follicles. This layer contains Meissner corpuscles or nerve endings sensitive to touch. Deeper layers contain a matrix of collagen that contributes to elasticity. An example would be skin stretching during pregnancy or the stretching that occurs with swelling post injury. This layer contributes to the formation of epidermal ridges that form the loops and whorls found on palms commonly called

fingerprints. Deep within dermis are cutaneous receptors for touch, pressure, pain. There are a variety of other structures, each with its own pathway to the brain

Function and Function of the Hair The primary function of the hair is to protect the skin. It is found most notably on the head, eyebrows and genitalia but also more slightly on legs and arms. Hair is composed of dead keratinized cells bonded together by extracellular proteins. The shaft of straight hair is round, and oval in curly hair. The hair follicle has a root or bulb that extends into the dermis. There is a sebaceous or oil gland for each individual hair. A smooth erector muscle moves the hair shaft and surrounding skin in response to a cold temperature by forming goose bumps on the skin. The hair shaft may also become erect during frightening situations in which the hair on the back of neck stands up. This is the autonomic nervous system fight or flight to a threatening or potentially dangerous situation. Function and Structure of the Nails A healthy fingernail functions to protect the soft tissue found at the ends of the fingertips and toes. In the fingers it serves to provide protection when pressure is exerted to the pulp side of the fingertip.



Nails are tightly packed keratinized epidermal cells covering the dorsal surfaces (back sides) of the fingers and toes. The nail body is visible with the free edge extending past the end of the digit. The nail bed appears pink because of underlying blood capillaries. The lunula or half-‐moon white area is a thicker non-‐transparent layer of basal cells.

Accumulation of Fat Cells Cellulite is the accumulation of fat cells in both the epidermal and the dermal layers of the skin. Cellulite gives the skin a “cottage cheese” appearance. It seems to accumulate in the thighs and buttocks. Wound Healing Wound healing is a normal activity of the body to repair itself. Wounds heal from the deepest layer outwards to the

most superficial ones. Epidermal healing is the first step in healing of superficial wounds and the last step in the healing of deep wounds with no scar formation. During the first phase of epidermal healing there is bleeding and clot formation. This phase involves enlargement and migration of basal cells across the wound from opposite sides forming a matrix for new cell growth.

In dermal healing there are four phases of wound healing include:

• bleeding • inflammation • proliferation of cells in deeper layers • remodeling

Bleeding is visible from the epidermal layer but the source of the blood is in the deeper layers depending on the severity of the injury.



Inflammation is a vascular and immune response to eliminate microbes and dying cells. A clot becomes a scab with migration of epithelial cells. Fibroblasts migrate along fibers and damaged blood vessels begin to repair. Proliferation is the extensive growth of new epithelial cells that replace the scab. This sometimes results in an atrophic (abnormal) accumulation of tissue called a scar. During the remodeling phase the scab sloughs off and collagen fibers become more organized (normotrophic).

Wound Healing in Burns A burn is tissue damage caused by excessive heat, electricity, radioactivity or corrosive chemicals. Burns may involve different layers of the epidermis and the dermis and are classified by the depth of wound. Second and third degree burns, depending on the extent of the surface area of damage, may involve systemic effects including of loss of water and blood plasma which may result in systemic shock, bacterial infection, reduced blood circulation, and impaired immune response.

Aging and the Integumentary System The skin, like every system in the body, changes over time and age. Normal “aging” results in reductions in muscle strength, cell division activity, hormonal levels, blood circulation and general metabolic activities. Aging changes in the skin are reflected in the thinning of the epidermis, loss of elasticity and resilience in the dermis leading to slower wound healing, and loss of fat in the hypodermis revealing itself as thinning and sagging skin and changes in thermoregulation.

This concludes Chapter 3: The Integumentary System. Answer the following questions before proceeding to the next chapter.



Exam: Integumentary System Select one or more correct answers 1. Which is NOT a function of the skin: ___a. protection ___b. excretion ___c. absorption ___d. thermoregulation ___e. metabolism 2. In thermoregulation, ___a. sweat on the surface causes cooling. ___b. sweat adjusts blood flow in the dermis. ___c. sweat may regulate temperature due to internal inflammation. 3. The three primary layers of the skin are: ___a. epidermis ___b. collagen ___c. dermis ___d. subcutaneous 4. The role of melanin includes: ___a. synchronization of circadian rhythms ___b. blood pressure regulation ___c. skin color ___d. mitochondrial DNA protection ___e. important in scar formation 5. The ___________ layer contributes to formation of ridges that form whorls and loops of fingerprints. ___a. epidermis ___b. dermis ___c. subcutaneous 6. Receptors for touch, pressure and pain are found in the: ___a. epidermal layer ___b. dermal layer ___c. subcutaneous layer 7. The nail bed appears pink due to: ___a. bruising ___b. underlying capillaries



___c. hangnails 8. Cellulite is formed in which layer? ___a. epidermis ___b. dermis ___c. subcutaneous 9. Remodeling is usually the last phase of wound healing. ___a. True ___b. False 10. Severe wounds heal first from the surface then to deeper layers. ___a. True ___b. False



Chapter 4: Respiratory System The respiratory system is responsible for delivering oxygen to the blood and removing carbon dioxide from the body. Pay particular attention to the interdependency of the respiratory, musculoskeletal, circulatory, and nervous systems.

Learning Objectives

} Identify the primary functions of the Respiratory System

} Identify component parts of the upper respiratory tract and their functions

} Identify component parts of the lower respiratory tract and their functions

} Recognize the difference between inspiration and expiration

} Explain the function of the diaphragm in breathing

} Understand how oxygen we breath gets into the blood stream

Functions of the Respiratory System

The respiratory system facilitates the breath of life, literally. It provides for gas exchange through the intake of oxygen (O2) and the elimination of carbon dioxide (CO2). This process helps regulate blood pH (potential Hydrogen). Oxygen attaches to red blood cells passing through the vasculature of the lungs and is transported to every cell in the body. The respiratory system also contains the receptors for the sense of smell. The Upper Respiratory Tract

During inhalation, air enters the body through the nose. Inside the nasal cavity nasal hairs called cilia imbedded in the sticky mucous membrane prevent the passage of large debris, like dirt, from entering the lungs.

Next, air passes into the sinuses which are lined with cilia that constantly move debris and mucous toward the throat to be swallowed. They are hollow chambers that also provide resonance chambers for the human voice. Sinuses are lined with mucous membranes that can respond to allergens and bacteria with inflammation and pain.

Capillaries (tiny blood vessels) beneath the nasal epithelium warn air before it enters the lungs. Deep in the nasal cavity is olfactory tissue used to detect odors.



The eustachian tube connects directly to the middle ear; when blocked, inflammation occurs. This is commonly called an earache.

The soft palate is a muscular-‐membranous structure, actually part of the digestive system. During swallowing the soft palate is raised like a trap door to close off upper airway passages.

Other structures of the upper respiratory tract include the nasopharynx, pharyngeal tonsil (adenoid), oropharynx, to name a few. This complexity begins to explain the specialty called ears, nose, throat (ENT).

The Lower Respiratory Tract

Two lung structures occupy the thoracic (chest) cavity. The left lung has two lobes (sections) and tends to be smaller to make room for vascular connections to the heart. The right lung is divided into three lobes. Lungs are protected by the skeletal structure known as the rib cage. Larynx connects the pharynx to the trachea and helps regulate the passage of air to and from the lungs. It contains the flexible piece of cartilage called the epiglottis which covers the trachea (windpipe) to prevent swallowed items from entering the lungs. It is comprised of three pieces of cartilage: thyroid , laryngeal prominence (Adam’s apple), and cricoid. When the larynx becomes inflamed, the voice is compromised and is commonly known as laryngitis.

The trachea is the main air passageway from the nose and mouth into the lung. It divides into two major branches called bronchus which again divide into many smaller bronchioles that feed the alveoli. The alveoli are small grape-‐like structures often referred to as the respiratory zone. These structures are directly involved in the gas exchange of oxygen and carbon dioxide in the blood.

Source: www.opentrax.org



How Oxygen Gets into the Blood

There are billions of alveoli in each lung surrounded by tiny blood capillaries. Oxygen passes through the alveoli membrane wall and attaches to hemoglobin in the red blood cells. At the same time, carbon dioxide is passed from the blood into the lungs for exhalation. A special chemical known as a surfactant keeps the wall of the alveoli wet to facilitate the exchange of gases between alveoli and blood capillaries.

Gas Exchange

Oxygenated blood carried on the hemoglobin is circulated to organs and tissues throughout the body. Gaseous by-‐products of cell metabolism, mainly carbon dioxide, are exhaled by the lungs.

Breathing

Inhaling and exhaling or “breathing” is an involuntary process controlled by the nervous system through the medulla deep in the brainstem. Intercostal nerves activate the muscles that control breathing causing the expansion and contraction of the rib cage and the up-‐down movement of the diaphragm. Breathing is a two-‐step cycle accomplished by manipulating the pressure gradient between the surrounding atmosphere and the thoracic cavity. Inhalation refers to a process in which the negative pressure inside the thoracic cavity forces the diaphragm to move down and the costal muscles to contract, moving the ribs to allow the lungs to expand. Exhalation occurs when there is a positive pressure inside the thoracic cavity causing the diaphragm to move upward while the costal muscles relax reducing the air space in the lungs.

Source: www.nuffieldfoundation.com



Lung Capacity

Total lung capacity is the total volume of air in the lungs after one deep inhalation. The tidal volume refers to air exchange during normal breathing. Vital capacity is the air exchanged during total filling and emptying of the lung. And, residual volume is the amount of air remaining in the lungs after deeply forced exhalation.

Respiratory Rate

Respiratory status is often measured as rate of breaths per minute. This is counted as one full inhalation and exhalation cycle. Average resting respiratory rates by age are:

• birth to 6 weeks: 30–60 breaths per minute • 6 months: 25–40 breaths per minute • 3 years: 20–30 breaths per minute • 6 years: 18–25 breaths per minute • 10 years: 17–23 breaths per minute • Adults: 12-‐18-‐breaths per minute • Elderly ≥ 65 years old: 12-‐28 breaths per minute. • Elderly ≥ 80 years old: 10-‐30 breaths per minute.

This concludes Chapter 4: The Respiratory System. Answer the following

This concludes Chapter 4: The Respiratory System. Answer the following questions before proceeding to the next chapter.



EXAM: Respiratory System

Select one or more correct answers. 1. Identify the primary functions of the respiratory system. ___a. contains receptors for smell ___b. provides for gas exchange (intake of oxygen, elimination of carbon dioxide) ___c. helps regulate blood pH (potential hydrogen) 2. One of the functions of the nasal cavities is to warm the air as it enters the nose. ___a. True ___b. False

3. Identify components of the lower respiratory system. ___a. larynx ___b. trachea ___c. bronchioles ___d. sinuses ___e. eustachian tube 4. Gas exchange (oxygen) takes place in which part of the lung? ___a. bronchus ___b. bronchioles ___c. alveoli

5. Which lung has only two lobes? ___a. right lung ___b. left lung 6. Oxygen is carried on ______________ . ___a. white blood cells ___b. red blood cells ___c. ATP 7. During the “flight or fight” response the sympathetic nervous system causes muscles to enlarge the bronchial branches allowing more oxygen into the lungs. ___a. True ___b. False

8. Inhalation is characterized by ____________________________________. ___a. negative pressure inside the thoracic cavity ___b. downward motion of the diaphragm ___c. upward motion of the diaphragm ___d. expansion of costal rib muscles



9. After one exhales as much as possible there is still air in the lungs called the vital capacity. ___a. True ___b. False 10. The gaseous by-‐product of cell metabolism is called: ___a. ATP ___b. carbon dioxide ___c. oxygenation



Chapter 5: Circulatory System In this chapter we explore the structure of the heart and its role in circulation. In addition, will look at how the heart and lungs work together to oxygenate tissue cells, the differences between arteries and veins, and the function of the blood that runs through the cardiovascular vessels.

Learning Objectives

} Identify the primary function of the Circulatory System

} Describe the differences between how blood flows in the left side and right side of the heart

} Identify the four chambers of the heart and their function

} Identify the purpose of the ventricles

} Describe arterial and venous flow of blood through the heart

} Explain differences between the structure of arteries and veins

} Describe the function of the capillaries

} Identify the primary components of blood and their function

} Explain the three phases of blood clotting

Anatomy of the Circulatory System The heart is the major organ of the circulatory system and is located behind the sternum or breastbone and between the lungs. It is built with specialized cardiac muscle tissue that pumps blood oxygenated by the respiratory system. The anatomy of the circulatory system include the heart, blood, arteries and veins, and is commonly referred to as the cardiovascular system. The cardiovascular system provides a vast network of vessels throughout the body supplying blood to every bone, muscle, organ, tissue and the brain. It is estimated there are over 60,000+ miles of blood vessels in an adult body. The heart pumps approximately 14,000 liters of blood daily which is approximately 2.6 million gallons of blood sent through those vessels yearly.



} Chambers of the Heart

The heart is composed into two major sections separated by the septum making the two parts anatomically and functionally different. The right side of the heart receives deoxygenated blood from systemic veins and pumps it to the lungs. The left side of the heart receives oxygenated blood from the lungs and pumps blood to the body. The upper two chambers of the heart are called the atria. They contract or relax at the same time. The lower chambers of the heart are called the ventricles, they also contract or relax at the same time. An electrical impulse called an action potential triggers the heart muscle contraction and originates in the heart itself (not the brain). In the atrium, this action potential originates in a structure called the SA node or sinoatrial node, known as the heart’s pacemaker. In the ventricles the action potential originates in the atrioventricular (AV) node.

} Valves of the Heart Heart valves open allowing blood to exit the chambers and close preventing that prevent “back flow” of blood into the chambers. The tricuspid valve on the right prevents blood from re-‐entering the right atrium. The mitral valve, also called the bicuspid valve, keeps blood from re-‐entering the left atrium. There is a pulmonary semilunar valve that prevents back flow into the pulmonary artery. The aortic semi-‐lunar valve prevents backflow into the aorta.

} Blood Flow Through the Heart Blood from the superior vena cava empty oxygen poor blood into the right atrium. The right atrium contracts and blood moves into the right ventricle thru the tricuspid valve. The right ventricle contracts and blood leaves the heart through the pulmonary valve into the pulmonary artery going to the lungs where it gets oxygenated. Pulmonary vein empties oxygen rich blood into the left atrium. Blood flows to the left ventricle through the mitral valve. Ventricular blood flows through the aortic valve which splits to splits to go to the upper body and to the lower body. Blood is then circulated through the capillaries where oxygen is used in cellular metabolism. Deoxygenated blood flows through the veins into the inferior and superior vena cava and the cycles begins again.



} Structure of Arteries and Veins Arteries carry oxygenated blood away from the heart and branches into smaller and smaller vessels eventually becoming capillaries where nutrients and wastes are exchanged at the cell level. Metabolic waste and deoxygenated blood enters venules (small veins) and is carried back to the heart through larger vessels called veins.

The smooth muscle in these blood vessel walls are responsible for maintaining the pressures and volume of the blood flow to and from the heart. Veins are built with valves to prevent the backflow of blood as it ascends to the heart.

} The Capillary System Capillaries are the tiniest blood vessels. Blood flow through the capillaries is called microcirculation. The function of the capillaries is to exchange nutrients and waste through the interstitial fluid. Distribution varies with metabolic activity of the tissue. (Muscles, kidneys and the nervous system are highly vascular tissues because they use more oxygen and nutrients.) Capillary walls are only one cell in thickness allowing easy passage of nutrients which also makes them highly susceptible to damage from physical or chemical forces. The outer wall of venules and veins (tunica externa) is thicker preventing re-‐absorption of waste products. Physiology of the Circulatory System

The primary function of the circulatory system is transportation: movement of blood, fluids, waste products, and nutrients into and out of every cell in the body. This transportation momentum is created by the pumping action of the heart muscle. The system also transports cellular waste products to the appropriate organ for removal. Two other functions include defense and maintaining homeostasis. The blood defend the body by supplying white blood cells to fight against invading microbes and platelets which prevent blood loss from damaged blood vessels. Blood maintains homeostasis by regulating body temperature and maintaining chemical balance.



} Blood Pressure and the Cardiac Cycle

The heart muscle contracts and relaxes. The time between the contraction of the atria and the relaxation of the ventricles is known as the cardiac cycle. Contraction is systole. Relaxation is diastole. Blood pressure measures the cardiac cycle, that is, the pressure difference between the systolic and diastolic cycle. Good blood pressure assures efficient blood flow to the body. In a reading of 120/80, 120 refers to the systolic pressure and 80 refers to diastolic pressure. During the systole stage the heart pumps oxygenated blood to the body and deoxygenated blood to the lungs. During the diastole stage the heart fills with oxygenated blood from the lungs and the deoxygenated blood from the body. These pressures reflect the resistance of the peripheral vasculature system which gives clue to the stresses placed on the vasculature and the ability (or inability) of the vasculature to deliver nutrients and remove waste efficiently.

} The Heartbeat and Systemic Blood flow The heart rate measures the number of times per minute the heart muscle is stimulated to contract. The rate at which the cells of the SA node (pacemaker) discharge their action potential to trigger this contraction originates in the heart but is influenced by the autonomic nervous system (ANS). The Composition of Blood Blood is composed of formed elements (red blood cells (RBCs), white blood cells (WBCs) and cell fragments called platelets) and a unique liquid called plasma. Its main function is to deliver oxygen and nutrients throughout the body and remove metabolic waste. Additionally, blood is responsible for providing defense for the organism, distribute heat, and maintain homeostasis.

} Blood Cells Red blood cells contain hemoglobin molecules and are solely responsible for carrying oxygen to cells. Once delivered, deoxygenated red blood cells return to the heart to be sent to the lungs for re-‐

Normal, average heart rates: • Adult rate at rest is 60-‐74 • Child rate at rest is 100-‐120



oxygenation. Platelets are a type of blood cell that play a vital role in blood clotting. White blood cells (called leukocytes) are part of the immune system defense response.

} Blood Plasma Plasma, the liquid substrate of blood, is more than 90% water. It contains a mixture of proteins mostly produced by the liver: albumin, globulins and fibrinogen. One type of globulin, known as immunoglobulins (or antibodies) are produced by plasma leukocytes, not the liver. Plasma globulins carry iron, lipids, fat-‐soluble vitamins and essential trace mineral micronutrients such as calcium, zinc, phosphorus and copper. Plasma transports glucose absorbed in the intestines to give the body a source of energy.

} Hemostasis (Blood Clotting) Hemostasis (blood clotting) is the body’s natural response to blood vessel injury. It occurs in 3 stages:

• Stage 1: Vascular Spasm -‐ When an artery or arteriole is damaged a chemical message is sent out and smooth muscles immediately contract to reduce blood loss. This contracture (or spasm) is typically accompanied by activation of the pain response (part of the defense function).

• Stage II: Platelet Release Reaction -‐ Platelets are activated by the chemical release from the injury site. Platelets change their morphology (shape) and become sticky allowing them to group together and stick to parts of damaged blood vessel creating what is called a platelet plug.

• Stage III: Platelet aggregation (coagulation) – At the site of the platelet plug interconnecting fibers (fibrinogen) forming a matrix that is reinforced by fibrin threads until an initial clot is formed.

This concludes Chapter 5: The Circulatory System. Answer the following questions before proceeding to the next chapter.



EXAM: Circulatory System

Select one or more correct answers 1. Function(s) of the circulatory system include: ___a. transport electrical signals from vessels to nerves ___b. transport waste produces of cell metabolism ___c. transport nutrients from digestive tract ___d. transport oxygen from the lungs 2. The right side of the heart pumps blood through the lungs. ___a. True ___b. False

3. Upper chambers of the heart are called the ventricles. ___a. True ___b. False 4. An electrical impulse which controls the heartbeat originates in the brain. ___a. True ___b. False 5. Valves in the arteries prevent back flow of blood into the heart. ___a. True ___b. False

6. Blood pressure is a reflection of the balance between systolic and diastolic pressure of the heart measured through blood flow in the arteries. ___a. True ___b. False 7. Number the order in which blood flows through the heart. ___a. oxygen depleted blood enters right atrium then moves it to right ventricle ___b. pulmonary vein empties oxygen rich blood into left atrium ___c. right ventricle moves blood to lung ___d. left ventricle sends oxygen rich blood to the aorta 8. The heart rate in children is typically faster than adults. ___a. True ___b. False



9. Function of the capillaries is to: ___a. provide nutrients to organs ___b. return blood to the heart ___c. remove cell waste ___d. aid in fighting infection 10. ____________ play(s) a role in fighting infection. ___a. White blood cells ___b. Red blood cells ___c. Plasma



Chapter 6: The Lymphatic System

The lymphatic system and the immune system work hand to destroy and eliminate pathogens from the body. The lymphatic system is a network of vessels, cells and organs that filters pathogens and removes excess fluids from the blood.

The immune system uses this exact network to mount the body’s defense to neutralize or destroy pathogens with its highly specific cellular response.

Learning Objectives

} Describe the general function of the lymphatic system

} Identify primary lymphatic organs

} Identify the organization of lymphatic vessels

} Describe the formation and flow of lymph

} Identify the role of the lymphatic system in the immune system response

} Recognize the organs associated with immune functions

Structures of the Lymphatic System

} Lymphatic Vessels

The structure of the lymph vessel is similar to veins with more valves and thinner walls. Lymphatic vessels are located in the subcutaneous layer of the skin and generally follow the vascular pathways. Lymphatic vessels in organs follow the arterial pathway forming a concentration around them. The lymphatic system drains excess fluid from tissue spaces and returns dietary lipids, glucose, oxygen and amino acids back to the bloodstream. Movement of lymph is dependent upon muscle activity and microcirculation. Unlike the circulatory system, the lymphatic system has no pump.



} Lymphatic Nodes The bean shaped lymph node is located along the lymph vessels. Lymph nodes are vital to the immune response and called secondary lymphoid organs numbering between 500 – 600 throughout the body. Lymph nodes are concentrated in the axilla (armpit), the groin and under the jaw. Swelling of lymph nodes Is often a sign of inflammation – the initial phases of an immune response.

} Lymphatic Capillaries

Lymphatic capillaries are larger than blood capillaries and are found throughout the body with the exception of: cartilage, the epidermis, the cornea of the eye, the central nervous system, the spleen and red bone marrow. Their unique structure permits interstitial fluid to flow in but not out. Functions of the Lymphatic System The primary function of the lymphatic system structures is to drain excess body fluids from interstitial spaces (outside of cell walls) and return it to the bloodstream. This interstitial fluid is called lymph. Blockages in the flow of lymph leaves this excess fluid in the tissue and is called lymphedema. Additionally, the lymph node structures are vital staging location for the immune system response. White blood cells known as lymphocyte are the mediators of the adaptive immune response. Identified as B-‐cells or T-‐cells, these lymphocytes originate in the bone marrow and migrate through the blood stream to the lymphatic system and reside in the lymphoid organs (spleen and lymph nodes). A third type of lymphocyte, the plasma cells, gain the ability to secrete antibodies after exposure to pathogens. Another lymphocyte, called the natural killer cells (NK), is a circulating blood cell and among the first lines of defense against viruses and certain cancers.



} The Thymus Gland The primary lymphoid organs are the bone marrow and the thymus. The thymus gland is a small butterfly shaped organ lying behind the sternum and in front of the heart. Immune system T-‐cells mature in the thymus gland. T-‐cells defend the body from potentially deadly pathogens such as bacteria, viruses and fungi. In infants the gland is quite large preparing the body for a lifetime of protection. After puberty adipose (fat) and connective tissue begin to replace thymic tissue.

} The Spleen

The spleen is a major secondary lymphoid organ although the largest mass of lymphatic tissue in the body. It is located on the left side between the stomach and the diaphragm. It is highly vascular, contains macrophages and lymphocytes (immune cells) and functions as a filter removing microbes and dying red blood cells from the blood. It can be damaged from abdominal trauma occurring in contact sports or automobile accidents. If damaged or removed, the liver and red bone marrow take over its functions.

} The Tonsils Tonsils are lymphoid nodules located in the inner surface of the pharynx. These structures are densely packed with lymphocytes and are important in the developing of immunity to oral pathogens. The adenoids, (the pharyngeal tonsil) is located at the back of the throat. Swelling indicates an active immune response to infection. Tonsils actually help children’s bodies develop immunity to common environmental pathogens.



This concludes Chapter 6: The Lymphatic System. Answer the following questions before proceeding to the next chapter.



Exam: Lymphatic System Select one or more correct answers 1. Pathways for lymphatic flow in the body follows similar pathways for circulatory system. ___a. True ___b. False 2. Lymph capillaries ______________________________ . ___a. are concentrated around organs ___b. connect with lymph nodes concentrated in the armpit and groin ___c. permit flow of interstitial fluid to the heart 3. Edema is excess fluid in the interstitial space between cells unable to enter the lymphatic system. ___a. True ___b. False 4. Function of the lymphatic system is to: ___a. drain excess interstitial fluid from tissue spaces ___b. cleanse the blood ___c. facilitate the immune response ___d. transport dietary lipids, glucose and amino acids 5. T-‐cells are a type of lymphocyte that matures in the: ___a. white blood cells ___b. red bone marrow ___c. thymus gland 6. Lymphocytes play a vital role in the immune response. ___a. True ___b. False 7. The antibody-‐immune response comes from ___________________________ . ___a. memory T cells that speed up reaction time ___b. natural killer cells that attack antigens ___c. lymphocyte B cells which secrete antibodies 8. Primary organs of the lymphatic system include the thymus and spleen ___a. True ___b. False 9. Liver is the largest mass of lymphatic tissue ___a. True ___b. False



Chapter 7: The Digestive System The digestive system, also known as the gastrointestinal track (GI), consists of many organs and structures: the mouth, esophagus, stomach, liver, gall bladder, pancreas, small and large intestines. We will only touched on the chemistry of the digestive system leaving the focus of this course on the location, function and interrelationship of these structures.

Learning Objectives

} Identify function of major organs of the digestive system } Recognize how food passes through the alimentary canal } Identify the six major processes of digestion

Structure and Function of the Digestive System Organs

The digestive system begins with the structures of the mouth and end at the last sphincter structure of the body, the anus. This passageway is called the alimentary canal, more commonly the gastrointestinal tract (GI). It is responsible for the breakdown of food and the assimilation of nutrients necessary to maintain life. It is also vitally connected every other body systems. Various chemical secretions, most notably digestive enzymes, provide the catalyst that breaks down food into micronutrients convertible to energy (ATP) needed for cellular function and amino acids for tissue growth and repair.

} Stages of Digestion There are five major stages of digestion. The first is called ingestion or taking food. It begins with the senses of sight and smell. When we see and smell our mouth begins to secrete saliva, one of the first enzymes to breakdown food. The grinding and crushing of food is accomplished by the premolar and molar teeth. Chewing mixed with saliva is called mastication, a process in which food is broken down into smaller pieces as the surface area of the food increases and enzymatic activity begins to break the food particles down into the needed micronutrients. The epiglottis is a structure which drops down when swallowing to ensure food does not enter an airway. Food then passes into the esophagus which begins the second stage called propulsion or the



movement of food through the digestive system. The third stage of digestion involves the mechanical and chemical breakdown of food. The fourth stage is called the assimilation phase involving the absorption of nutrients. The final stage of digestion is elimination or the removal of waste products.

} Swallowing When food is adequately broken down and thoroughly wet with saliva the bolus of food is moved reflexively by the tongue pressing against soft palate, the posterior part of the roof of the mouth. This causes the hyoid bone (Adam’s apple) to move upward allowing the food to pass through the pharynx on its way to the esophagus. The soft palate also serves as a “trap door” so that food does not enter the air passage-‐ way, causing “choking.”

} Propulsion Propulsion of food from the mouth to the stomach passes through the esophagus with wave-‐like motions called peristalsis. Because of this anti-‐gravity muscular action, food can be swallowed in zero gravity or even when the body is upside down (not recommended). Peristalsis is the involuntary muscular movement of food throughout the GI track. Disruptions in lower GI peristalsis result in condition called obstruction.

} Digestion – Mechanical Breakdown

While digestion begins in the mouth with chewing, the bulk of the digestive processes happen once the food reaches the stomach. The pH in the mouth and esophagus is very basic (high pH) but once it reaches the stomach it becomes very acidic (low pH) because of hydrochloric acid (HCL). The stomach muscles work on the bolus of food mixing it with HCL and breaking it into chyme before it enters the duodenum.



} Digestion – Chemical Breakdown Chemical breakdown begins but does not end with the stomach. Chemical breakdown involves enzymes, the most of which are produced in the pancreas, which act as catalysts to speed up the process.

} Structure and Function of the Stomach

The stomach links the esophagus to the first part of the small intestine, the duodenum. The lower esophageal sphincter is a muscle that surrounds the bottom of the tube and serves like a valve that opens and closes. The stomach, empty, is about the size of your fist. It has the elasticity to expand to up to 75 times its empty size and return to normal size when empty. Stomach size is not correlated to body weight. The stomach is essentially a holding chamber for ingested food. Digestion begins here, but is completed in the lower parts of the GI track.

} Structure and Function of the Pancreas

The pancreas is a small dense highly vascular organ located underneath the liver on the right side of the body. The pancreas is intimately involved in hormone production in the body, most notably insulin. It also produces a variety of digestive enzymes that flow into the duodenum and contribute to the chemical breakdown of the digestive process. Amylase (also found in saliva) aids in the breakdown of starches that come from carbohydrates. Lipase breaks down fats. Protease breaks down proteins while trypsin digests proteins. Cellulase is an enzyme that breaks down cellulose, the carbohydrate that is the main part of the cell wall of plants.

Cellulose is mostly indigestible but provides fiber that moves wastes through the intestines.

Foodstuff Enzyme End Product Carbohydrate Amylases Simple Sugar Lipids (fats) Lipases Fatty acids Proteins Proteases Amino acids



} Structure and Function of the Liver

The liver is the heaviest gland in the body and the second largest after the skin. It is located in the upper right quadrant of the abdominal cavity beneath the diaphragm and is protected by the rib cage. There are two lobes of the liver, the left being smaller than the right. It’s two main vessels, the hepatic artery and the hepatic portal vein, connect the digestive system allowing it to the liver all bloodborne nutrients and toxins from the alimentary canal. The liver has fenestrated capillary spaces called sinusoids through which blood passes and filtration occurs. In these spaces phagocytes kill worn out leukocytes (white blood cells), red blood cells, and bacteria found in venous blood draining from the gastro-‐intestinal track. The liver produces bile, a yellow brownish olive-‐green liquid composed mostly of water, bile acids and cholesterol, which plays a major role in the breakdown of lipids in the small intestine. The liver contributes to normal blood glucose levels by breaking down glycogen into glucose and releasing it into the bloodstream. Lipid metabolism uses liver cells called hepatocytes to break down and synthesize fatty acids to be used in cholesterol production. The liver is the prime site for absorption and storage of vitamins A, B12, D, and E. Along with the liver, the skin and kidneys assist with synthesis of vitamin K.

} Structure and Function of the Gall Bladder

The gall bladder is a small pear-‐shaped organ nestled under the back side of the liver. The main function of the gall bladder is the storage and concentration of bile until it is needed by the small intestine.



Bile plays a role in emulsification or the breaking down of large fat globules. After emulsification most bile salts are reabsorbed in the final segment of the small intestine called the ilium and enter portal vein blood flowing back toward the liver. If bile contains insufficient bile salts or excessive cholesterol, the cholesterol may crystallize to form gall stones. This may inhibit flow of bile from the gall bladder into the small intestine. } The Small Intestine The majority of digestion, absorption and assimilation, takes place in

the small intestine. The small intestine is essentially a long tube which provides a huge surface area for absorption. It begins at the pyloric valve of the stomach and ends as it opens into the large intestine. The surface area is increased by folds in the intestine. The small intestine absorbs all carbohydrates as monosaccharides (many sugars). Proteins are absorbed as amino acids a process that occurs at the beginning (duodenum) or middle of the small intestine (jejunum). Most lipids are absorbed via simple diffusion. Most electrolytes (calcium, potassium, iodine, etc.) that are absorbed come from gastrointestinal secretions. Fat soluble vitamins A, D, E and K are also absorbed through simple diffusion. Small intestine absorbs water, with the remaining components passing into the large intestine.

} The Large Intestine The large intestine is terminal portion of the gastrointestinal (GI) tract. It forms an inverted “U” shape in the lower anatomy. Its overall function is completion of absorption, production of certain vitamins, and the formation and expulsion of solid waste products called feces. Any disruption of the peristalsis in this organ results in the conditions ranging from simple constipation to more serious obstruction.



Processed particles pass from the small intestine through the ileum into the cecum. This waste material then travels through the ascending colon to the transverse colon and down the descending colon where is passes through the sigmoid colon to the rectum and exits the body through the anus. Final stages of digestion occur through bacteria activity that ferments any remaining carbohydrates and releases hydrogen, carbon dioxide, and methane gas converting any remaining proteins into amino acids which are transported back to the liver and excreted as toxins through the urine. Little is known of the role of the appendix in digestion. One theory suggests it may serve as a store house good for “good” bacteria. When inflamed it creates appendicitis, a condition commonly requiring surgical removal.

This concludes Chapter 7: The Digestive System. Answer the following questions before proceeding to the next chapter.



EXAM: Digestive System Select one or more correct answers 1. Primary purpose of digestion is to: ___a. breakdown consumed food ___b. circulation of energy from assimilation ___c. convert food into micronutrients for energy production ___d. provide micronutrients for growth and repair of body tissues 2. There are 5 stages of digestion with include: ___a. ingestion ___b. propulsion ___c. assimilation ___d. detoxification

3. Digestion begins when food enters the stomach. ___a. True ___b. False 4. Peristalsis is the wave-‐like motion that moves food through the entire GI tract. ___a. True ___b. false 5. The lower esophageal sphincter opens when food is passed from the esophagus into the stomach. ___a. True ___b. False

6. Carbohydrates are broken into amino acids in the stomach. ___a. True ___b. False 7. Food processed by the digestive system includes: ___a. carbohydrates ___b. proteins ___c. water ___d. lipids

8. _____________ enzymes break down starches. ___a. Liver ___b. Pancreatic ___c. Gall bladder



9. Cellulose is _________________________________________. ___a. sugar converted to energy for activation of ATP ___b. an enzyme that stimulates vitamin production ___c. an ingestible fiber that moves wastes through the intestine

10. One of the functions of the _______ is the production of bile. ___a. gall bladder ___b. pancreas ___c. liver 11. Majority of digestion takes place in the_______________. ___a. stomach ___b. liver ___c. pancreas ___d. large intestine ___e. small intestine

12. Final stage of digestion occurs through action of bacteria ___________________. ___a. secreted from the bile ___b. found in the large intestine ___c. that absorbs vitamins and minerals through the small intestine



Chapter 8: Urinary System While there are not many organs in the urinary system, the kidneys are perhaps one of the most complex organs in the body and is intricately connected to the cardiovascular system. We have limited the discussion of the chemistry involved in kidney function and focused on general function.

Learning Objectives

} Identify the organs of the urinary system

} Identify the structure and function of the kidneys

} Identify structure and function of the bladder

Structures of the Urinary System

The urinary system consists of two kidneys, two ureters, one urinary bladder, and one urethra. The kidneys lie on the posterior abdominal wall area are protected by muscle, fat and ribs. The Kidneys

} Structure and Function of the Kidneys

Kidneys are highly vascularized and dependent on cardiac output. There are 2-‐3 million “groups” of specialized capillaries called glomeruli in the functional unit of the kidney called the nephron. The

nephrons provide filtration of the blood secreting waste products and returning useful substances to the blood performing a reabsorption function. While kidneys do the work of making and passing urine to the bladder, they have a much broader and important function in the body. The kidneys regulate blood pressure by adjusting blood flow through the kidneys. They perform this function by conserving or eliminating water. An increase in blood volume causes an increase in blood pressure while a



decrease in blood volume causes a decrease in blood pressure. The kidneys are important in regulating blood ionic composition regulating the levels of sodium, potassium, calcium, chloride and phosphate. This maintains blood osmolarity referring to the number of dissolved particles per liter of solution. The kidneys regulate blood pH homeostasis and excrete wastes products from the body through the production of urine. There are four steps in the formation of urine.

• First, blood enters the renal capsule where filtration begins.

• Second, solutes and water are reabsorbed into the blood flow through renal capillaries.

• Third, waste products are secreted. • Finally, processed urine is sent to the ureters

where it is transported to the bladder.

The kidneys release two very important hormones unrelated to urine production and management: calcitriol and erythropoiesis. Calcitriol is an active form of vitamin D which regulates calcium levels in the body. Erythropoiesis (EPO) stimulates the bone marrow to produce red blood cells. Reduction in kidney function is one of the primary causes of anemia (low red blood counts).

The Ureters

} Structure and Function

Each of two ureters transport urine from one kidney to the urinary bladder. There is no anatomical valve at the opening of either ureter into the urinary bladder. Rather, movement from the body requires the interplay between hydrostatic pressure, gravity and peristalsis of the muscular walls within the ureters. The Bladder

} Structure and Function As the urinary bladder fills with urine from the kidneys, pressure within it compresses the openings of the ureters and prevents backflow of urine into the kidneys. Discharge of urine involves voluntary and involuntary muscle contractions.



Passage of urine occurs in a number of stages. • First, the bladder fills from kidney discharge. • The bladder enlarges an sends a message

along nerves to the brain signaling an urge to release urine.

• If the signal is recognized the bladder may be emptied voluntarily.

• If the signal is initially ignored, the bladder will continue to fill sending a more urgent signal to the brain.

• If the signal is ignored and overfills or not recognized at all the bladder empties involuntarily.

The release of urine without voluntary control may be the result of weakened sphincter muscles or neurologic damage and is called urinary incontinence.

This concludes Chapter 8: The Urinary System. Answer the following questions before proceeding to the next chapter.



EXAM: Urinary System Select one or more correct answers 1. Primary organs of the urinary system are: ___a. kidney ___b. liver ___c. bladder ___d. ureter ___e. urethra 2. The ____________ carries urine from the kidney to the bladder. ___a. ureter ___b. urethra ___c. nephron

3. The function of the kidneys is to _________________________. ___a. regulate blood pressure ___b. regulate blood pH ___c. release an enzyme that regulates calcium ___d. removes waste products from the blood 4. Discharging urine from the bladder involves only voluntary muscles. ___a. True ___b. False

5. Incontinence is most often related to ___a. blockage in urethra ___b. weakened sphincter muscles or neurologic damage ___c. dehydration 6. Reduction in kidney function is one of the primary causes of anemia. ___a. True ___b. False



Chapter 9: The Endocrine System The endocrine system and the nervous system control all functions of the body. The functional units of the endocrine system are hormones. We will focus on the structure and function of the most important organs and what they regulate.

Learning Objectives

} Identify the major glands and tissues of the endocrine system and their location in the body

} Name the major hormones and their regulatory effects

} Understand the stress response mediated through the nervous system and managed by the endocrine system

Structure and Function of the Endocrine System

The nervous system and endocrine system are the communication systems (software) that coordinate all functions in the body. The nervous system controls activities through nerve impulses sent along nerve fibers. At synapses, nerve impulses trigger the release of mediator molecules called neurotransmitters. (to be discussed in detail in Chapter 10) In contrast, the glands of the endocrine system release mediator molecules called hormones. The circulating blood delivers hormones to every cell in the body. These hormones regulate the body’s growth and metabolism, sexual development and function. The fascinating thing is that hormones can also be neurotransmitters. The endocrine system regulates activity of smooth muscles, cardiac muscle, glandular activity, essentially affecting all cells in the body. It also affects tissues that alter metabolism, regulate growth, and influence the reproductive process.



In comparing the endocrine system with the nervous system notice differences in cells affected and reaction time. All cells in the body may be affected by the endocrine system and the hormonal influence may last from seconds to days. Glands of the Endocrine System The body contains two kinds of glands: Exocrine and endocrine. Exocrine glands secrete products into ducts (channels) that carry secretions into body cavities or the outer surface of the body (like sweat glands). Endocrine glands secrete hormones into the interstitial fluid surrounding the cells which then diffuses into capillaries and are carried by the blood to the target tissues. Hence, endocrine signaling can take seconds to days to cause target cell responses. The primary glands of the endocrine system are the pineal, pituitary, thyroid, parathyroid, and adrenal. Other organs that secrete hormones include the hypothalamus, thymus, pancreas, ovaries & testes. Hormones affect specific target cells binding to a protein (receptor cell) and operate within a delicate feedback loop. When a hormone is produced in excess the target cell will down regulates the hormone production; if it is depleted, the target cell will send a message to up-‐regulate the hormone production.

} The Pineal Gland The pineal gland is a small pinecone shaped gland deep within the brain. One of the major hormones secreted by the pineal gland is melatonin which is released when the eyes perceive sustained darkness, typically with sunset. Melatonin release is linked to the body’s biological clock called circadian rhythms. This includes daily sleep-‐wake cycles as well as seasonal cycles. Some researchers suggest low sunlight exposure in winter months may contribute to a condition called “Seasonal Affective Disorder “(SAD).

Characteristic Nervous System Endocrine System

Mediator molecules

Neurotransmitters Hormones

Cells affected Muscles, Glands All Cells in the body

Time Within milliseconds Lasts briefly

Seconds to days Lasts longer



} The Pituitary Gland

The pituitary gland is a pea shaped structure attached to the hypothalamus. While very small it is one of the most powerful glands in the body and has been called the master gland. It is divided into two parts: the anterior pituitary and the posterior pituitary -‐ each with its own set of hormones. Many hormones secreted by this gland that are influenced by the releasing or inhibiting signaling hormones of the hypothalamus. The hormones of the anterior pituitary include:

• human growth hormone (HGH) stimulates body growth and regulates metabolism

• thyroid stimulating hormone (TSH) has a major role in metabolism

• follicle stimulating hormone (FSH) stimulates estrogen and progesterone in the reproductive cycle

• prolactin (PRL) stimulates milk production in mammary glands

• adrenocorticotropic hormone (ATCH) stimulates the adrenal cortex to produce cortisol and other hormones.

Functions of the posterior pituitary are quite different. It does not synthesize any hormones; it stores and releases them.

• Oxytocin, the female hormone contracts the uterus after birth and stimulates milk ejection. • Antidiuretic Hormone (ADH) decreases urine production and returns more water to the blood.

ADH can be increased through pain, stress, trauma, nicotine, morphine, some tranquilizers and anesthetics.

} The Hypothalamus Gland

The hypothalamus is located near the midbrain and pituitary gland. The hypothalamus serves as the link between the nervous system and the endocrine system. Often considered the hypothalamus-‐



pituitary complex, it receives input from the nervous system and the thalamus. It also receives sensory signals from the internal organs and the retina of the eye.

The hypothalamus in located in and receives input from the limbic system, a region of the brain involved with emotional responses and memory function. The amygdala gland (group of nuclei) is “safety central” sitting atop the brain stem sending signals to the hypothalamus to stimulate the sympathetic fight or flight response. Consequently, painful, stressful and emotional experiences cause changes in activity of the hypothalamus. The hypothalamus signals the autonomic nervous system to regulate body temperature, thirst, hunger, sexual behavior and

protective/defense reactions. The hypothalamus also regulates growth, metabolism and maintains homeostasis throughout the body.

} The Thyroid Glands The butterfly shaped thyroid glands lie below the voice box and on either side of the trachea. They product two primary hormones: thyroxine and triiodothyronine. Triiodothyronine (T3) regulates oxygen use and basal metabolism rate, cellular metabolism and cellular growth and development. Thyroxine (T4) is a type of iodine. The release of T3 and T4 is regulated by thyroid stimulation hormone (TSH) from the pituitary gland in an elaborate feedback loop. The thyroid also secretes a hormone called calcitonin which contributes to calcium homeostasis in the blood.

} The Parathyroid Glands Attached to the posterior surface of the thyroid gland are four small round masses of tissue called the parathyroid glands. These glands secrete the parathyroid hormone (PTH). This hormone stimulates osteoclast activity in the bones. The result is elevated bone reabsorption which releases calcium and phosphates into the blood. The parathyroid hormone also increases the rate at which kidneys remove calcium and magnesium from urine and produce calcitriol, an active form of Vitamin D.



} The Adrenal Glands The adrenal glands are small pyramidal shaped glands that sit on top of each kidney. The major function of the adrenal glands is to respond to stress, both physical and emotional, in the effort to respond and restore safety and maintain homeostasis in the body. Adrenals produce hormones from two different layers: the medulla (center) and the cortex (outer). The cortex secretes hormones for regulation of long-‐term stress responses. The medulla secretes epinephrine and norepinephrine in an immediate stress response mediated by the sympathetic nervous system. The primary hormones are:

• Mineralocorticoids regulate the mineral, water and electrolyte balance. • Glucocorticoid regulates glucose metabolism • Androgens secreted from the adrenal cortex secrete dihydroepiandrosterone (DHEA) a major

contributor to sex drive, particularly in females • Catecholamines include epinephrine and norepinephrine which mimic effects brought about by

the sympathetic nervous system.

} The Pancreas

The pancreas is primarily an exocrine gland secreting many digestive enzymes. Its major role as an endocrine gland lies in its regulation of blood glucose levels with the production and secretion of the hormones glucagon, insulin, somatostatin, and pancreatic polypeptide.

• Glucagon increases blood glucose when levels fall below normal.

• Insulin lowers glucose levels when too high. • Somatostatin inhibits both glucagon and insulin as needed. • Pancreatic polypeptides inhibit somatostatin, gall bladder

contraction and pancreatic polypeptide digestive enzymes.



} The Ovaries The female gonads, called ovaries, are paired oval bodies located in the pelvic cavity. While part of the female reproductive system producing ova, they secrete gonadal hormones in a feedback loop with pituitary hormones to regulate the female reproductive cycle, maintain pregnancy and prepare mammary glands for lactation. They produce two hormones: estrogens and progesterone. These hormones are responsible for the development and maintenance of female sex characteristics, regulation of the menstrual cycle, and maintenance of pregnancy. Ovaries also produce small amounts of the male hormone testosterone.

} The Testes The male has two oval gonads called testes. They produce the gonadal hormone called testosterone which regulates sperm and stimulates development of secondary sex characteristics including deepening of the voice, body hair, and increased body muscle mass. Testosterone inhibits secretion of FSH from the anterior pituitary gland.



The Stress Response The body’s response to stressful or threatening stimuli demands all hands on deck. The stress response links functions of the endocrine and nervous systems and subsequently all other systems in the body. Remember, the principle driving force of the human body is survival. A stressor may be any disturbance of the body’s normal, homeostatic status: heat or cold, environmental poison exposure, allergens, bacterial or viral infections, heavy bleeding from a wound or surgery, a strong emotional reaction to a real or perceived threat, even the very subtle electromagnetic field interference through WIFI and cell towers. When the external environment influences fluctuates within normal boundaries of pressure or temperature for example, stress is thought to be a healthy response and homeostasis is easily reestablished. That is, not all activation of the ANS is caused from being chased by a tiger! Putting in a good workout on a treadmill gets the heart beating faster, breathing to change, sweat to appear, and hunger to be postponed, temporarily. When the stimuli exceeds what is normal and the amygdala gland perceives the situation as potentially life threatening, the ANS fight, flight or freeze response is initiated. This signaling chemistry affects every single cell in the body via the sympathetic and parasympathetic nervous system. The stress response typically occurs in three stages: alarm, resistance, and exhaustion



} Alarm Reaction The alarm reaction is a set in motion by signals from the amygdala gland to the hypothalamus. The alarm reaction mobilizes the body’s resources for immediate action putting every organ in the body on high alert. Large amounts of glucose are dumped into the blood stream. Breathing changes increasing oxygen intake. Sympathetic tone diverts oxygen from the periphery to the central organs, brain, and large muscles. The heart pumps more blood to brain and muscles preparing for fight or flight. Overall there is increase in ATP for cellular energy driving the system for ample supplies of oxygen and glucose. During the fight or flight response all nonessential physiologic activities are down regulated – digestive, urinary, and reproductive systems activities are reduced. Essentially the sympathetic system is highly activated while the parasympathetic system is more dormant. There is, however, one other response to the threat during the alarm reaction: freeze. This is a most complicated physiologic response because BOTH the parasympathetic and sympathetic nervous systems are activated at the same time. The outcome has the body “frozen” for the moment. Think playing opossum.

} Resistance Stage The second phase of the stress response is the resistance stage initiated by the hypothalamus. In a series of chain reactions like falling dominoes, the release of corticotropin releasing hormone (CRH) stimulates the anterior pituitary to increase ATCH which stimulates the adrenal cortex to lower body pH and conserve potassium which leads to water retention in the kidneys. ATCH stimulates conversion of carbohydrates into glucose, enhances protein breakdown and makes blood vessels more sensitive to stimuli that brings about their constriction (sympathetic tone). The growth releasing hormone (GHRH) from the hypothalamus stimulates the anterior pituitary to activate the human growth hormone (hGh) converting glycogen into glucose for usable energy. The thyrotropin releasing hormone (TRH) causes the anterior pituitary to stimulate the thyroid gland to stimulate T3 and T4 to supply additional ATP for metabolism. This stage is meant to end once the threat has disappeared.



} Exhaustion Stage

If the resistance phase is successful and the body survives the “attack”, the body will move into a state of parasympathetic relaxation in order to repair and restore its reserves for the next battle. Enzyme and circulatory changes return to normal. There are circumstances when the actual threat is gone yet the body is unable to end the resistance phase. A kindling of the alarm and resistance chemistry is still directing bodily functions. Eventually the body enters the exhaustion stage meaning the body has lost its ability to re-‐establish homeostasis and disease occurs. Most of the chronic diseases have their etiology in an unrelieved, trauma related stress response.

This concludes Chapter 9: The Endocrine System. Answer the following questions before proceeding to the next chapter.



EXAM: Endocrine System Select one or more correct answers.

1. The ____________ receives input from the amygdala gland in the limbic system. ___a. pituitary ___b. pineal ___c. hypothalamus ___d. thalamus 2. Endocrine glands secrete hormones directly into other glands and cells. ___a. true ___b. false 3. Melatonin regulates the body’s biological clock and is produced in the _________ gland. ___a. pineal ___b. hypothalamus ___c. pituitary 4. Anterior pituitary regulates: ___a. human growth ___b. production of estrogen and progesterone ___c. water retention ___d. ATCH in the adrenal gland 5. Oxytocin, the female hormone, is stored and regulated by the _____________________ . ___a. ovaries ___b. adrenal glands ___c. posterior pituitary 6. Thyroid glands secrete T3 which regulates: ___a. oxygen use ___b. cell metabolism ___c. immune responses ___d. growth & development ___e. emotions triggered by the stress response 7. Parathyroid glands produce hormones that: ___a. are stimulated by stress, trauma, nicotine, & morphine ___b. are increased through decreased urine production ___c. affect the ability of the kidney to remove calcium and magnesium from the urine ___d. stimulate the kidneys to form calcitriol, an active version of VIT D



8. Adrenal glands produce hormones that: ___a. contribute to sex drive ___b. influence pH (acid base balance) in the blood ___c. control water balance ___d. regulate resistance to stress 9. Which of the following is a major digestive organ and manages blood sugar? ___a. adrenals ___b. kidney ___c. pancreas ___d. thyroid 10. The stress response includes several stages which are: ___a. resistance reaction ___b. assimilation ___c. alarm phase ___d. exhaustion



Chapter 10: The Nervous System The nervous system is the master control center for the human body and another of the most complex systems in the body. The focus is on the differences between the central nervous system and the peripheral nervous system, the sympathetic and parasympathetic nervous systems, the limbic system and the function of the four main parts of the brain: cerebrum, cerebellum, diencephalon, and brain stem.

Learning Objectives

} Identify the basic parts of a neuron

} Understand pathways to and from the brain for sensory and motor nerves

} Identify groups of nerves called plexus that go to the upper and lower limbs

} Describe the difference between the peripheral nervous system and the central nervous system

} Identify function of the two parts of the autonomic nervous system

} Identify main parts of the brain and their function

} Describe the function of the four main parts of the brain

} Explain function of limbic system

} Identify brain structures and function of those associated with memory

} Recognize major function of 12 cranial nerves

Structure and Function of the Nervous System

The nervous system is the most complex system in the body as it controls the functioning of all other systems. It uses two types of intercellular communication -‐ electrical and chemical. By way of contract to the endocrine system, the target cells respond in milliseconds to signaling from the nervous system.

} Neurons, Dendrites and Axons

Neurons are the basic unit of the nervous system. They are composed of a cell body that contains the nucleus surrounded by cytoplasm containing the mitochondrion -‐ the energy production centers of the cell. Dendrites or “little trees” are the receiving portion of the neuron. The



axon is the message pathway of the neuron sending nerve impulses to other neurons, muscle fibers, or gland cells. The axon is encased in a protein covering called the myelin sheath which speeds the nerve impulse to the axon terminal.

Neurons have the property of electrical excitability. Neurons produce action potentials or impulses in response to stimuli. Once stimulated, the action potential propagates (moves) from one point to the next along the plasma membrane via specific ion channels. The site of communication between two neurons is called a synapse. The swollen or bulb shape synapse stores a chemical called a neurotransmitter. Neurotransmitters influences the activity of other neurons, muscle fibers, or gland cells.

} Neurotransmitters Neurotransmitters are amino acids linked by peptide bonds called neuropeptides. Neurotransmitters are the chemical signaling molecule of the nervous system. They are produced in the neuron cell body and transported to the axon terminals. Common neurotransmitters in the brain are: glutamate, GABA, dopamine, serotonin, acetylcholine, norepinephrine, and many more. Some neurotransmitters play the dual role as hormones. One of the most common peptides is called an endorphin, which serves as a natural pain killer in the body. Another neuropeptide that functions like a hormone is called cholecystokinin, found in the brain and small intestine; it regulates the “stop eating” cycle by excreting a pancreatic enzyme.

} Anatomy of a Nerve A nerve is actually a bundle of nerve fibers surrounded by blood vessels and a myelin sheath -‐ a lipid and protein covering that provides insulation to speeds nerve transmission. Schwann cells form myelin in the peripheral nervous system. Oligodendrocytes form myelin in the central nervous system. Nerves may have synapse and end at the spinal cord or may have ascending and descending nerve tracts to the brain.



Organization of the Nervous System

The chart below offers a basic overview of the organization of the nervous system.

The Nervous System

Peripheral Nervous System Central Nervous System

Somatic Nervous System Autonomic Nervous System Spinal Cord Brain

Sympathetic Nervous System Parasympathetic Nervous System

Peripheral Nervous System

The peripheral nervous system is composed of two distinct neural pathways: the somatic nervous system and the autonomic nervous system. The somatic nervous system is concerned with voluntary control of muscles and spinal reflex activity. The autonomic nervous system functions automatically, that is, without conscious awareness (involuntarily).

} Somatic Nervous System – Sensory Pathway

Motor nerves control motion while the sensory nerves carry sensations of heat cold, pressure, touch and pain. Both the sensory and motor nerves pass through the spinal cord on the way to and from the brain. The sensory pathways are ascending tracts as they go from nerve endings in the periphery “up” to the brain. They pass through the medulla oblongata and “switch” sides – left sensations to the right side of the brain; right sensations to the left side of the brain. Certain sensory nerves that respond to temperature, touch, pressure and pain have specific connections at the spinal cord level allowing for an even quicker (involuntary) motor response.

Cross Section of spinal cord



Sensory messages that ascend to and reach the somatosensory cortex in the brain trigger response in the motor cortex which descends to the peripheral muscle fibers causing either contraction or relaxation. Hence, the motor pathways are descending pathways as they go from the brain through the spinal column “down” to the peripheral nerves to invoke muscle response. The spinal cord contains the cervical plexus that innervates the lower brain and neck, the brachial plexus that innervates the shoulders, arms and hands and the lumbar plexus and sacral plexus that innervate the lower back, legs and feet.

} Somatic Nervous System – Motor

Pathway The descending motor pathway from the brain to the extremities also crosses at the medulla. The right side of the brain controls the left side of the body & vice versa. White matter tracts send motor impulses from the brain back to the peripheral parts of the body. Major motor pathways from the brain to the extremities have similar names as pathways found in the circulatory system and the skeletal system.



} Dermatomes

Dermatomes are another way of looking at somatic sensory and motor pathways. The skin over the entire body is supplied by sensory neurons that carry nerve impulses to the spinal cord and brain stem. The underlying skeletal muscles are innervated by somatic motor neurons. Dermatomes provide innervations to specific segments of the body. Knowing which spinal cord segments supply each dermatome makes it possible to locate damaged regions of the spinal cord.



Autonomic Nervous System

The autonomic nervous system (ANS) is the second part of the peripheral nervous system. The ANS regulates activity of smooth muscles, cardiac muscles and glandular tissue. It’s primary purpose is the survival of the organism and in collaboration with the endocrine system the ANS is vital to maintaining homeostasis in the body. The ANS operates without conscious control (hence the term autonomic) from a constant flow of input from the body. Interestingly, meditation and breathing as demonstrated by master yogi teachers exert some levels of conscious control over this otherwise subconscious (involuntary) system. The ANS is regulated by centers in the brain, mainly the hypothalamus and brain stem. These centers are constantly receiving input from the limbic system and other regions of the cerebrum. It is divided into two distinct systems: the parasympathetic and the sympathetic nervous systems. These nerves enervate every organ in the body and affect very different responses.



} The Parasympathetic Nervous System

The parasympathetic nervous system is associated with rest, digestion and recovery. It maintains homeostasis in the body in close collaboration with the sympathetic nervous system. It is also part of the freeze response to real or perceived danger. The parasympathetic system is often referred to as the craniosacral system because its neurons are located in the brain stem and the sacral spinal cord.

• Cranial Nerve III Oculomotor nerve • Cranial Nerve VII Facial nerve • Cranial Nerve IX Glossopharyngeal nerve • Cranial Nerve X Vagus nerve which is the

only nerve that exits the skull and goes to all organs of the body)

• Spinal connections are through the splanchnic nerves from the sacral spine (S2, S3, S4).

} The Sympathetic Nervous System The sympathetic nervous system controls the “fight, flight or freeze” response to both external or internal stressors. Notice that the sympathetic spinal control comes from the thoracic region of the spinal cord and is sometimes referred to as the thoracolumbar system. Thoracic connections go directly through major nerve centers called ganglia which line both sides of the vertebral column extending from the base of the skull to the base of the spine. NOTE: The medulla oblongata houses the centers for both parasympathetic and sympathetic activation of cardiac tissue. During rest both centers provide slight stimulation to the heart creating autonomic tone.



The Central Nervous System

The central nervous system contains the brain and spinal cord. The brain is the source for processing thoughts, emotions and memories governed by the lobes of the brain. The spinal cord contains different fibers depending on their location in the spinal cord. The dorsal or posterior root contains sensory fibers that connect impulses from the periphery to the CNS. The ventral or anterior root contains the motor neurons from the CNS.

} The Cervical Spine

The Cervical Plexus (C1-‐5) supplies head and neck C 2 Lesser Occipital Nerve -‐ skin and scalp around the ear C 2-‐3 Great Auricular Nerve -‐ skin around the ear and parotid glands C2-‐3 Transverse Cervical Nerve -‐ skin over the front of neck C3-‐4 Supraclavicular Nerve -‐ skin over the chest and shoulders C3-‐5 Phrenic Nerve -‐ controls the diaphragm located between the thorax and the abdomen

The Brachial Plexus (C5-‐T1) supplies the shoulders and upper limbs C 5, 6, 7 Supply the muscles of the shoulder, upper back and chest C5-‐T1 Median Nerve innervates the flexors of the forearm and hand C5-‐8 Radial Nerve innervates the extensors of the forearm and hand C8-‐T1 Ulnar Nerve innervates the flexors of the forearm and hand



} The Thoracic Spine The thoracic spine has nerve innervations to the chest and abdomen. It does not form a plexus, rather there is direct innervation at the spinal level. There is both an anterior and posterior nerve root with slightly different innervated areas. Nerve roots carry separate sensory and motor tracts.

} The Lumbar Spine The Lumbar Plexus (L1-‐5) supplies the abdominal wall, external genitals and part of the lower limbs. Innervations involve: L1 Iliohypogastric nerve -‐ muscles of abdominal wall L1 Ilioinguinal nerve -‐ abdominal wall, genitals, skin of thigh L1-‐2 Genitofemoral nerve -‐ genitals, skin over the thigh L2-‐3 Lateral Femoral Cutaneous nerve -‐ skin over the thigh L2-‐4 Femoral nerve -‐ flexor of thigh, leg extensors L2-‐4 Obturator nerve -‐ muscles of abdominal wall, skin of the upper thigh L4-‐S3 Sciatic nerve -‐ This is the largest nerve in the lower body composed of two nerves bound together by a sheath of connective tissue. It descends through the thigh sending branches to the hamstring muscles. L4-‐S3 Tibia nerve – This is the prime motor supply for muscles of the lower leg. Branches of this nerve in the foot are called plantar nerves. L4-‐S2 Common Peroneal nerve -‐ Supplies muscles of the lower leg.



The Sacral Spine The Sacral Plexus (L5-‐S4) supplies the buttocks, perineum and lower limbs as follows: L4-‐5 Superior gluteal nerve supplies gluteus minimus muscles L5-‐S2 Inferior gluteal nerve supplies gluteus maximus muscle S2-‐1 Nerve to piriformis muscle -‐ rotates the thigh at the hip joint L4-‐5, S1 Nerve to quadratus femoris rotates and stabilizes hip joint L5-‐S2 Nerve to obturator -‐rotates thigh at hip S1-‐3 Posterior femoral cutaneous innervates the skin of the thigh S4-‐5 Pudendal nerve supplies male and female genitals. The Brain (part of the Central Nervous System)

Solving an equation, feeling hungry, and breathing are all mediated by different parts of the brain. The brain is the center for registering sensations, coordinating them with other sensations, storing information, making decisions and taking actions. It is the center for intellect, emotions, behavior, memory and consciousness. There are four main parts of the brain: cerebrum, cerebellum, diencephalon, and brain stem. } The Cerebrum

The cerebrum is the largest area in the brain. It contains the frontal, temporal, parietal, and occipital lobes of the brain. The longitudinal fissure separates the cerebrum into two distinct halves – a right and left hemisphere. The two hemispheres are connected by the corpus callosum. Sensory cortex interpret sensory information, the motor cortex controls muscular movement via their descending pathways. The basal ganglia coordinates automatic muscle movements. The



diencephalon extends from the brain stem to the cerebrum and serves as the link between the nervous system and the endocrine system.

} The Cerebellum Located at the back of the brain and attached to the brain stem and near the visual cortex, the cerebellum is responsible for voluntary motor movements, balance, equilibrium and muscle tone. It “balances” information from the cerebrum with information from the peripheral nervous system and sends out proprioceptive information about movements of the body.

} The Diencephalon The diencephalon is a subcortical region of the brain that contains the thalamus and the hypothalamus. It also includes the pineal gland. It is the relay station for the five senses communicating the information to the amygdala gland and the cerebral cortex. Part of the limbic system, this center is intimately connected to the autonomic nervous system.

} The Brain Stem The brain stem connects the brain and the spinal cord. It contains the medulla oblongata, pons, and midbrain. Both ascending and descending nerve pathways travel through the brain stem. The gray and white matter found indicate its essential purpose: to process cranial nerve information.

} The Limbic System The limbic system lies deep within the cerebrum. It governs emotional aspects of behavior related to survival. It plays a role in processing a wide range of emotions including pain, pleasure, docility, affection and anger. The hippocampus which is part of the limbic system has a major role in the formation of memory. The amygdala, part of the reptilian brain, has a primary role in the fight, flight, freeze survival response. It is basically preverbal and controls autonomic functions associated with the sympathetic nervous system. Impulses are very primal and instinctual.

} Hemispheres of the Brain

The left hemisphere of the brain functions like a serial processor. Neurons fire one at a time so that events appear to occur in sequential order. It is thus concerned with processing time and ordering events. In most people it is the site for processing both speech and the understanding of language.



The right hemisphere is hard wired as a parallel processor so that impulses appear in groupings and can occur simultaneously. It is almost as if the “picture” is not understood until all the puzzles pieces are in place. This means that the “ah-‐ha” or sudden realization of connections is a phenomena of the right hemisphere. It is thus the site of synchronicity – where events may appear at the same time. It is believed to be concerned with processing space and special properties of objects in relationship to each other as near, far, over, under, and beside.

} The Lobes of the Brain The frontal lobes are concerned with what is called “executive functions” or how the brain thinks. It is involved with problem solving, judgment, planning, anticipation, speaking, emotional expression, awareness of abilities, self-‐monitoring skills, personality, social behavior, behavior control, setting limitations, organization, attention, initiation of activities, and concentration. The parietal lobes on both side of the head lie behind the frontal lobes. They are concerned with perception and play a role in recognition of visual and auditory stimulation. They process sensory information dealing with touch, taste and smell; differentiation of size, shape, and color; spatial and visual perception and the academic skills used in math calculations, reading and writing.

Temporal lobes are located on both sides of the head just above the ears. They too are involved with perception and the recognition of auditory stimuli. They play a vital role in expression of speech and formation of



memories. They also play a role in the understanding of language, Information retrieval, musical awareness, memory, hearing, learning, and the expression of feelings.

Occipital lobe at the back of the brain is involved with processing visual stimuli and forming it into visual memories. It plays an important role in visual reception, visual interpretation, reading, and recognition of visual stimuli.

Functions of the Cranial Nerves

} Cranial Nerve I: Olfactory nerve concerned with smell } Cranial Nerve II: Optical nerve that processes vision, proprioception, and controls eye

movement } Cranial Nerve III: Oculomotor nerve } Cranial Nerve IV: Trochlear nerve also involved in proprioception, eye movement } Cranial Nerve V: Trigeminal nerve has three branches in the face:

o Ophthalmic Nerve: in the forehead which innervates the eye o Maxillary Nerve: supplies the upper jaw, lip and teeth o Mandibular Nerve: innervates the tongue, lower jaw, and side of the head

} Cranial Nerve VI: Abducens nerve is also involved in proprioception, and eye movement } Cranial Nerve VII: Facial nerve } Cranial Nerve VIII: Vestibulocochlear nerve – transmits sound and equilibrium (balance) } Cranial Nerve IX: Glossopharyngeal nerve } Cranial Nerve X: Vagus nerve which is the only nerve that exits the skull and goes to all

organs of the body) Special Senses

} Vision The visual pathway has axons extending from the thalamus to the occipital lobe at the midbrain level. Following the red pathway in the illustration, information from the right side of the visual field and the nasal side of the left eye is processed in the right hemisphere of the brain. Following the green pathway the opposite is true for visual processing in the left hemisphere of the brain. This unique pattern of innervation protects the body so that if the right eye is completely damaged the left eye will still have some level of binocularity.



In cases where there is damage to the brain itself, as in a stroke, the person will have difficulty scanning the field causing frequent collisions when passing through doorways and when attempting to follow printed words when reading from left to right.

} Hearing Hearing is the process of collecting sound waves and interpreting them in the brain. The outer ear acts much like a funnel to collect and transmit sound waves. The middle ear conveys sound vibrations to the eardrum. The inner ear houses structures and receptors for hearing and equilibrium making the position of the head in space influential in balance and coordination.

This concludes Chapter 10: The Nervous System. Answer the following questions to complete the Anatomy and Physiology course work.



EXAM: Nervous System 1. What are the basic parts of a neuron? ___a. cell body ___b. dendrites ___c. axons ___d. synapse 2. The site of communication between two neurons is called: ___a. axon ___b. synapse ___c. mitochondria ___d. synaptic cleft

3. ___________________ is a natural pain killer peptide (neurotransmitter). ___a. dopamine ___b. acetylcholine ___c. endorphin 4. Certain sensory nerves for heat, cold, pressure, touch, and pain have specific connections at the spinal cord level. ___a. True ___b. False 5. Ascending and descending tracts in the spinal cord cross from one side of the body to the other at the medulla. ___a. True ___b. False

6. The spinal cord contains plexus or bundles of nerves that go the extremities. These are called: ___a. cervical plexus ___b. brachial plexus ___c. thoracic plexus ___d. lumbar plexus ___e. sacral plexus 7. Peripheral nervous system includes the brain and spinal cord. ___a. True ___b. False 8. Autonomic nervous system includes ___a. Somatic Nervous System ___b. Sympathetic Nervous System ___c. Parasympathetic Nervous System



9. Of the 12 cranial nerves, only the Vagus nerve exits the skull and goes to organs of the body. ___a. True ___b. False

10. Four principle parts of the brain are: ___a. cerebrum ___b. diencephalon ___c. cerebellum ___d. brain stem ___e. medulla 11. Which nervous system is associated with the “flight or fight” response? ___a. Somatic Nervous System ___b. Parasympathetic Nervous System ___c. Sympathetic Nervous System

12. The parasympathetic system: ___ a. constricts pupils ___b. constricts bronchi ___c. accelerates heartbeat ___d. stimulates peristalsis ___e. contracts bladder 13. The phrenic nerve high in the neck (C3-‐5) controls the diaphragm for breathing. ___a. True ___b. false

14. The brachial plexus supplies the shoulder, upper back, chest, and arm. Names of major nerves in this plexus are: ___a. median nerve ___b. thoracic nerve ___c. radial nerve ___d. ulnar nerve 15. Largest nerve in the lower body is the _____________________ . ___a. femoral nerve ___b. tibial nerve ___c. Vagus nerve ___d. sciatic nerve ___e. gluteal nerve

16. The medulla oblongata is an important brain structure because: ___a. it relays motor impulses from the brain to the body ___b. it relays sensory impulses from body to the brain ___c. it regulates heartbeat, blood vessel diameter, breathing



17. Limbic system, deep in the brain, houses the amygdala gland and governs ___a. primitive behavior related to survival ___b. has a role in pain, pleasure, affection and anger ___c. contributes to the “fight or flight” response of the Sympathetic Nervous System ___d. behaviors may be instinctual, ritualistic and/or repetitive 18. __________ in the spinal cord sends sensory impulses from the body to the brain. ___a. White matter ___b. Gray matter 19. Brain structure(s) that contribute to the memory is/are: ___a. hippocampus ___b. limbic system ___c. amygdala 20. Intuitive, holistic, creative activities are processed in the __________________ . ___a. left hemisphere ___b. right hemisphere 21. Brain structure(s) involved in proprioception include: ___ a. hypothalamus ___b. cerebrum ___c. cerebellum ___d. several cranial nerves



Congratulations! This completes your study of anatomy and physiology and a thorough examination of your understanding of the material.

Compare your answers to the Answers and Feedback handout provided as a separate document. Record your exam score on the course feedback form.

Passing the course with a score greater than 70% allows us to issue your “Certificate of Completion for Anatomy & Physiology”.

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