chapter one anatomy

Human Anatomy

The study of the structure of the human body.

Human Physiology

The study of the functions of the human body.

Chemical Level

The smallest level of organization where atoms combine to form molecules.

Cellular Level

Cells that differ in shape, size, and function.

Tissue Level

A group of similar cells and their extracellular matrix that perform a common function.

Organ Level

Two or more different types of tissues that come together to create a structure.

Organ Systems Level

A group of organs that work together to perform complex functions.

Organism Level

All organ systems functioning together to make up a living being.

Integumentary System

Protects, retains water, produces vitamin D, regulates temperature; includes skin, hair, and nails.

Skeletal System

Supports and protects the body, allows movement, produces blood cells, stores calcium; includes bones and joints.

Muscular System

Allows movement and generates heat; includes skeletal muscle.

Nervous System

Regulates body functions, sensation, movement, and mental function; includes spinal cord and nerves.

Endocrine System

Regulates body functions with hormones; includes ovaries, testes, pancreas, adrenal glands, and thyroid.

Cardiovascular System

Delivers oxygenated blood to the body, removes waste; includes heart and blood vessels.

Lymphatic System

Returns excess tissue fluid to the cardiovascular system and provides protection against disease.

Respiratory System

Delivers oxygen to the blood, removes carbon dioxide; includes nasal cavity, trachea, and lungs.

Digestive System

Digest food, absorb nutrients, and remove waste; includes mouth, stomach, and intestines.

Urinary System

Removes waste, balances fluid and electrolytes; includes kidneys and bladder.

Male Reproductive System

Produces and transports sperm, secretes hormones; includes prostate gland and testes.

Female Reproductive System

Produces and transports oocytes, supports fetal development; includes ovaries and uterus.

Systemic Anatomy

Focuses primarily on individual organ systems.

Regional Anatomy

Divides the body into regions for study.

Surface Anatomy

Studies the surface markings of the body.

Gross Anatomy

Examines structures visible to the naked eye.

Microscopic Anatomy

Studies structures that require a microscope.

Histology

The study of tissues.

Cytology

The study of cells.

Anatomical Position

Standing upright, facing forward, with arms at the sides.

Anterior

Toward the front of the body.

Posterior

Toward the back of the body.

Superior

Toward the head (only for head and trunk).

Inferior

Away from the head, toward the toes.

Proximal

Closer to the trunk or point of origin (used for limbs).

Distal

Farther from the trunk or point of origin.

Medial

Closer to the midline of the body.

Lateral

Farther away from the midline.

Superficial

Closer to the surface of the body.

Deep

Farther from the surface of the body.

Axial Region

Includes the head, neck, and trunk.

Appendicular Region

Includes the upper and lower limbs.

Sagittal Plane

Divides the body into right and left sections.

Midsagittal Plane

Divides the body into equal right and left halves.

Frontal Plane

Divides the body into anterior and posterior sections.

Transverse Plane

Divides the body into superior and inferior sections.

Posterior Body Cavity

Cavity located on the back side of the body.

Cranial Cavity

Cavity that houses the brain.

Vertebral Cavity

Cavity that contains the spinal cord.

Diaphragm Muscle

Muscle that separates the thoracic cavity from the abdominal cavity.

Abdominal Cavity

Cavity from the diaphragm to the bony pelvis.

Pelvic Cavity

Cavity within the bony pelvis.

Pleural Cavity

Cavity that surrounds the lungs.

Mediastinum

Cavity that houses the heart and great vessels.

Pericardial Cavity

Cavity that surrounds the heart.

Serous Membranes

Thin sheets of tissue that form body cavities.

Visceral Layer

The inner layer of a serous membrane that contacts the organ.

Parietal Layer

The outer layer of a serous membrane that attaches to surrounding structures.

Peritonitis

Infection of the peritoneal layer.

X-Ray

An imaging technique that uses ionizing radiation.

CT Scan

Uses ionizing radiation to produce a three-dimensional image.

MRI

Uses a magnetic field to produce a three-dimensional image.

Homeostasis

The body's ability to maintain a stable internal environment.

Feedback Loop

Homeostatic control mechanism where changes affect the same variable.

Positive Feedback Loop

Reinforces the initial change and increases output.

Negative Feedback Loop

Opposes the initial change and reduces output.

Set Point

The normal value for a regulated variable.

Stimulus

A variable that is outside its normal range.

Receptor

Alerts the control center to a stimulus.

Control Center

Receives stimuli and regulates outputs to effectors.

Effectors

Cause physiological responses that return variables to their normal range.

Principle of Complementarity of Structure and Function

The structure of a chemical, cell, tissue, or organ is designed to best suit its function.

Gradient

A difference in concentration, pressure, or temperature between two connected areas.

Cell Communication

Cells must communicate to ensure homeostasis.