Introduction to Anatomy and Physiology

Anatomy- the study of structure of an organism and the relationships of its parts

ana- apart -tomy to cut Gross anatomy- study of large,

easily observable structures Microscopic anatomy- study of small

structures that require magnification

Anatomy

Physiology – the study of how

the body and its parts function Physio- nature -ology the study of

Physiology

Anatomy and Physiology are

always related Structure determines function

Anatomy and Physiology Relationship

Levels of Organization

Chemical level- atoms and molecules

Cells- smallest living unit of structure and function

Tissue- groups of similar cells working together to perform a common function

Organ- two or more types of tissue arranged to perform a special function

Organ system- organization of varying number and kinds of organs grouped to perform complex functions for the body

Organism- all the organ systems working together

Organ System Overview

Integumentary- external covering of the body. It waterproofs, cushions, and protects the body. Also, aids in temperature control and houses various receptors to keep us alert

Skeletal system- consist of bones, cartilage, ligaments, and joints. It supports the body, provides a framework, and aids in movement. Plus, hematopoiesis occurs here and mineral storage.

Muscle system-The only function is to contract, which causes movement.

Nervous system- the body’s fast acting control center. Consisting of the brain, spinal cord, nerves and sensory receptors that detect and responds to various stimuli

Organ Systems cont.

Endocrine system- Slow or long acting control center composed of various glands that secrete hormones.

Cardiovascular system- primarily made up of the heart and blood vessels to transport nutrients and remove waste from throughout the body

Organ System cont.

Lymphatic system- complementary to the circulatory system with lymph vessel, lymph nodes, and special organs. Also, aids in immunity.

Respiratory system- keeps the body constantly supplied with oxygen through a variety of organs.

Digestive system- basically a

tube from the mouth to the anus that breaks down food into forms the body can use and get rid of what can not be used.

Urinary system/ excretory system- removes nitrogenous waste from the body, regulates water and salt balance, regulates acid-base balance in blood.

Organ System Cont.

Reproductive system- exist primarily to produce offspring. Males produce sperm and females produce egg and the uterus where fetus development occurs, after fertilization.

Maintaining boundaries- “insides”

must remain distinct from “outsides”.

Movement- not only does this include all activities promoted by the muscular system, it also includes the movement of substances in the body such as blood, nutrients, etc that are propelled through the cardiovascular, digestive and urinary system.

Maintaining Life

Responsiveness- the ability to sense

changes (stimuli) in the environment and then react to them. The nervous system bears the major responsibility for responsiveness

Digestion- process of breaking down ingested food into simple molecules that can then be absorbed into the blood for delivery to all body cells by the circulatory system.

Maintaining Life

Metabolism- a broad term that refers to

all chemical reactions that occur within body cells. Metabolism depends on the digestive, respiratory system, and cardiovascular systems to make the nutrients available to the body. It is also regulated by the endocrine system.

Excretion- the process of removing excreta (waste) from the body. Digestion and urinary systems play a large part in removing waste.

Maintaining life cont.

Reproduction- the process of maintaining

the species, not the survival of the individual. This is the task of the reproductive system and regulated by the endocrine system.

Growth- usually the increase of size but also includes development of the body as well. Various organ systems are working together so that cell-constructing activities are occurring faster than cell destroying ones. Also, regulated by the endocrine system.

Maintaining Life cont.

Nutrients- contain the chemicals used for energy

and cell building. Carbohydrates are the major energy providing fuel. Fats are essential for building cell structures, cushion body organs, and provide reserve fuel. Minerals and vitamins are required for the chemical reactions that go on in cells and for oxygen transport in the blood.

Oxygen- all nutrients are useless without oxygen! It is made available to the body from combined efforts of the cardiovascular and respiratory systems. It is needed for the chemical reactions that release energy from food.

Survival needs

Water- accounts for 60-80% of the

body weight. It is the single most abundant chemical substance in the body and provides a fluid base for body secretions and excretions. Water is obtained chiefly from ingested foods and liquids and is lost from the body by evaporation from the lungs and skin and in body excretions.

Survival Needs

Body Temperature- must be maintained around

37oC (98oF). As body temperature drops metabolism slows until it stops. When body temperature is too high chemical reactions proceed to rapidly and body proteins break down. At either extreme, death occurs. Most body heat is generated by the activity of skeletal muscles.

Atmospheric pressure-this is the force exerted on the surface of the body by the weight of air. Breathing and exchange of oxygen and carbon dioxide in the lungs depend on appropriate atmospheric pressure.

Survival Needs

Homeostasis is the relative constancy of the

internal environment. Two types of control systems

Negative feedback Most common Inhibitory Opposes a change

Ex. thermostat

Positive feedback Accelerates a change Child birth

Homeostasis

Anatomical position

The body is erect with the feet parallel and the arms hanging at the sides with the palms facing forward

The thumbs are pointing away from the body.

Anterior body landmarks pg. 13 Posterior body landmarks pg. 13 Orientation and directional terms pg. 14

Regional terms

Body planes and sections

Sagittal section- is a cut made along the longitudinal plane of the body Divides the body into left

and right sides If the cut is made down the

median plane of the body and the left and right sides are equal in size it is called a midsagital section.

Frontal section

Coronal section is a cut made along a lengthwise plane that divides the body into anterior and posterior parts

Frontal or coronal plane

Transverse section

Transverse plane is a cut made along a horizontal plane dividing the body into superior and inferior parts

Also called cross section

Body cavities

Two major portions Axial

Head, neck, and torso Torso composed of

thoracic, abdominal, and pelvic areas

Appendicular Upper and lower

extremities

Body Cavites

Dorsal body cavity Two subdivisions

Cranial Space inside the bony

skull Protects the brain

Spinal cavity Extends from the

cranial cavity nearly to the end of the vertebral column

Vertebrae surround the spinal cavity

Protects the spinal cord

Ventral body cavities

Subdivided into 2 regions Thoracic cavity Abdominopelvic

Abdominal pelvic

Thoraic Cavity

Thoracic cavity Separated from the

rest of the ventral cavity by the diaphragm

Organs protected by rib cage

Mediastinum separates the lungs into left and right cavities Houses the heart,

trachea, and other organs

Abdominopelvic cavity

Can be subdivided into superior and inferior

Abdominal cavity contains the stomach, liver, intestines, and other organs

Pelvic cavity contains reproductive organs, bladder, and rectum Not continuous with

abdominal cavity, tilts away from it in a posterior direction

Abdominal regions

Abdominal quadrants- divides the region into 4 more or less equal parts

Named according to relative position Right upper quadrant Left upper quadrant Right lower quadrant Left lower quadrant

Abdominal regions

Umbilical region Epigastric region Hypogastric region Right and left inguinal

regions Right and left lumbar

regions Right and left

hypochondriac region