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