Overview of Anatomy and Physiology

What is It? The branches of anatomy and physiology are complementary to each other Anatomy is the study of the structure of the body parts and their relationships with one another  Gross anatomy or macroscopic-study of LARGE body structures (those that would be visible with the naked eye)  Microscopic anatomy-cannot be seen with the naked eye, must use a microscope  Developmental anatomy traces structural changes that occur in the body through life (embryology) Physiology deals with the study of function of the body

Gross Anatomy Microscopic Regional anatomy- studies the structures in a particular region Systemic-system by system Surface-study of internal structures as they relate to the overlying skin Cytology-study of cells Histology-study of tissues The Subdivisions of Anatomy

Levels of Organization The human body has many levels of organization The most basic is the chemical level-at this level atoms combine to form molecules which will combine to make organelles Organelles make cells Cells make tissues Tissues make organs which in turn make organ systems

How Do We Live? Maintaining boundaries- internal environment remains distinct from external environments Movement Responsiveness (irritability)-ability to sense changes in the environment and respond Digestion Metabolism-breaking substances down Excretion-removing wastes Reproduction Growth Nutrition

Directional Terms Anatomical Position- The body is erect (standing up straight) with feet slightly apart and palms facing forward so that your thumbs point away from the body Note: the terms left and right refer to the position of the person being viewed NOT the observer

UP and DOWN Superior (Cranial) Inferior (Caudal) Toward the head or upper body (above) Away from the head or lower body (below)

FRONT and BACK Anterior (ventral) Posterior (dorsal) Toward or at the front of the body Toward or at the back of the body

In Between Medial Lateral Toward or at the midline of the body (inner side of) Away from the midline of the body (outer side of) Intermediate Between a more medial and more lateral structure

Extremities-UP and Down Proximal Distal Closer to the origin of the body part or point of attachment of a limb to the trunk Farther from the origin of a body part of the point of attachment of a limb to the body trunk

IN and OUT Superficial (external) Deep (internal) Toward or at the body surface Away from the body surface

Axial Appendicular Makes up the main axis of our body Includes head, neck and truck Consists of appendages (limbs) These are attached to the axis Regional Terms

Body Planes and Sections Sagittal Plane Frontal/coronal Plane A vertical plane that divides the body into right and left parts A sagittal plane that lies exactly in the midline is the midsagittal plane All other sagittal planes are called parasagittal planes (para-near) Lie vertically and divides the body into anterior and posterior parts Transverse/horizontal Plane Runs horizontally from left to right dividing the body into superior and inferior parts Sometimes these are referred to as cross sections

Body Cavities Dorsal Cavity  Protects the organs of the nervous system  Has TWO subdivisions: Cranial (skull) and Vertebral (spinal cord)  Because both of these are essentially part of the same organ, the two cavities are continuous with one another Ventral Body Cavity  More anterior and larger cavity  Houses internal organs collectively called the viscera  Has TWO major subdivisions: Thoracic (surrounded by ribs) and abdominopelvic (abdomen and pelvic regions)  The two major divisions are separated by the diaphragm

Subdivisions of Abdominopelvic Region Left/Right hypochondriac region: Part of the liver, gallbladder, & part of diaphragm in right; part of diaphragm and part of stomach in left Left/Right lumbar region: Ascending colon of large intestine in right; Descending colon of large intestine in left Left/Right iliac/inguinal region: Cecum of large intestine in right; Part of sigmoid colon of large intestine in left Epigastric Region: Most of the stomach Umbilical Region: Transverse colon of large intestine, small intestine Hypogastric/pubic Region: Bladder

Internal organs associated with abdominopelvic regions

Isolating the Organs Serous membranes:  consist of parietal layer and visceral layer

Dividing the Cavities Thoracic cavity: divided by the mediastinum into 2 pleural cavities

Organ Systems

Circulatory System FUNCTIONS: 1. Transports gases, nutrients, hormones, and waste. 2. Carries oxygen

Skeletal System FUNCTIONS: 1. Provides framework and protective shields for softer tissues. 2. Attachments for muscles. 3. Aids in movement. 4. Produces blood cells & stores inorganic salts.

Respiratory System FUNCTIONS: 1. Takes oxygen in and releases CO Exchanges gases between the blood and the air.

Nervous System FUNCTIONS: 1. Uses electrochemical signals to communicate. 2. Can detect changes inside and outside the body.

Muscular System FUNCTIONS: 1. Causes body movement. 2. Maintains posture. 3. Main source of body heat.

Lymphatic System FUNCTIONS: 1. Transports some of the tissue fluid back to the bloodstream. 2. Carries certain fatty substances away from the digestive organs.

Integumentary System FUNCTIONS: 1. Protects underlying tissues. 2. Helps regulate body temperature. 3. Houses sensory receptors. 4. Synthesizes certain products.

Excretory System FUNCTIONS: 1. Removes wastes from the blood. 2. Helps maintain the body’s water and electrolyte balance.

Endocrine System FUNCTIONS: 1. Secretes chemical messengers called hormones.

Digestive System FUNCTIONS: 1. Receives nutrients from the outside and break it down. 2. Produces hormones.