Anatomy and Physiology: Key Terminology

Vocabulary flashcards covering anatomical position, body planes, cavities and membranes, abdominal subdivision, body organization levels, organ systems, and homeostatic mechanisms.

Anatomic position

Standard reference position: body upright, feet together, arms at sides, palms facing forward.

Sagittal plane

Vertical plane dividing the body into left and right portions (midsagittal/median plane divides equally).

Frontal (coronal) plane

Vertical plane dividing the body into anterior (front) and posterior (back) portions.

Transverse (horizontal) plane

Horizontal plane dividing the body into superior (top) and inferior (bottom) portions.

Anterior

Toward the front of the body; also called ventral.

Posterior

Toward the back of the body; also called dorsal.

Superior

Toward the head or upper part of a structure; cranial.

Inferior

Toward the feet or lower part of a structure; caudal.

Medial

Toward the midline of the body.

Lateral

Away from the midline of the body.

Proximal

Closer to the point of attachment or origin.

Distal

Farther from the point of attachment or origin.

Superficial

Toward or at the body surface.

Deep

Away from the body surface; interior.

Dorsal body cavity

Posterior body cavity containing the cranial and vertebral (spinal) cavities.

Ventral body cavity

Anterior body cavity subdivided into the thoracic and abdominopelvic cavities.

Pleura

Serous membranes surrounding the lungs; consists of parietal pleura lining the chest wall and visceral pleura covering the lungs; pleural cavity contains pleural fluid.

Pericardium

Serous membrane around the heart; parietal pericardium lines the pericardial cavity and visceral pericardium covers the heart; pericardial cavity contains pericardial fluid.

Peritoneum

Serous membrane lining the abdominal cavity and covering abdominal organs; has parietal and visceral layers with peritoneal fluid.

Nine abdominal regions

Division into nine regions: right hypochondriac, epigastric, left hypochondriac; right lumbar, umbilical, left lumbar; right iliac, hypogastric, left iliac.

Four abdominal quadrants

Division into four quadrants: right upper, left upper, right lower, left lower.

Levels of organization

From simple to complex: chemical, cellular, tissue, organ, organ system, organism.

Chemical level

Atoms and molecules form the basic chemical substances of the body.

Cellular level

Cells, the basic units of life.

Tissue level

Groups of similar cells performing a common function.

Organ level

Structures composed of two or more tissue types working together.

Organ system level

Related organs integrated to perform major body functions.

Organism level

An individual living being resulting from all organ systems functioning together.

Integumentary system

Skin, hair, nails; protects the body, regulates temperature, and provides sensation.

Skeletal system

Bones and joints; supports and protects, aids movement, and forms blood cells.

Muscular system

Skeletal muscles that produce movement and maintain posture.

Nervous system

Brain, spinal cord, and nerves; controls body activities through electrical signals.

Endocrine system

Glands that secrete hormones regulating body processes.

Cardiovascular system

Heart and blood vessels; circulates blood and transports nutrients and wastes.

Lymphatic/immune system

Lymph nodes and vessels; returns fluid to blood and defends against infections.

Respiratory system

Lungs and airways; facilitates gas exchange.

Digestive system

Mouth to anus; digests food and absorbs nutrients.

Urinary system

Kidneys, ureters, bladder, urethra; removes wastes and maintains fluid balance.

Reproductive system

Organs involved in producing offspring.

Negative feedback

A homeostatic mechanism that reverses a change to return to a set point.

Positive feedback

A homeostatic mechanism that amplifies a change to reach a definite outcome.

Homeostasis

Maintenance of stable internal conditions within narrow limits.