Human Anatomy Structures, Systems, and Motions

Anatomy

The study of the structure of the body—what it’s made of, where things are, and how they’re arranged.

Physiology

The study of function—how biological structures work and what they do.

Levels of Organization

Biological organization spans from atoms to organ systems.

Respiratory System

One of the 11 systems of the body, responsible for the exchange of gases.

Digestive System

One of the 11 systems of the body, responsible for processing food and extracting nutrients.

Urinary System

One of the 11 systems of the body, responsible for waste removal and regulating water balance.

Reproductive System

One of the 11 systems responsible for producing offspring.

Endocrine System

One of the 11 systems that controls bodily functions through hormones.

Lymphatic/Immune System

One of the 11 systems that helps in defending the body against pathogens.

Integumentary System

One of the 11 systems that includes the skin and its derivatives.

Skeletal System

One of the 11 systems that provides structure and support to the body.

Muscular System

One of the 11 systems that enables movement through muscle contraction.

Cardiovascular System

One of the 11 systems responsible for transporting blood and nutrients throughout the body.

Nervous System

The body system responsible for sending signals between different parts of the body.

Body Cavities

Spaces within the body that house and protect internal organs.

Cranial Cavity

The space within the skull that contains the brain.

Vertebral Cavity

The space that houses the spinal cord.

Thoracic Cavity

The cavity within the chest that contains the heart and lungs.

Abdominal Cavity

The cavity that contains digestive organs.

Pelvic Cavity

The cavity that contains reproductive organs and urinary bladder.

Diaphragm

A dome-shaped muscle that separates the thoracic and abdominopelvic cavities.

Right Hypochondriac Region

Upper right region of the abdominopelvic area.

Epigastric Region

Upper center region of the abdominopelvic area.

Left Hypochondriac Region

Upper left region of the abdominopelvic area.

Right Lumbar Region

Middle right region of the abdominopelvic area.

Umbilical Region

Center region of the abdominopelvic area.

Left Lumbar Region

Middle left region of the abdominopelvic area.

Right Iliac Region

Lower right region of the abdominopelvic area.

Hypogastric Region

Lower center region of the abdominopelvic area.

Left Iliac Region

Lower left region of the abdominopelvic area.

Anatomical Position

A standard position where the body is standing upright, facing forward, with palms forward.

Proximal

Closer to the trunk of the body.

Distal

Farther from the trunk of the body.

Medial

Closer to the midline of the body.

Lateral

Farther from the midline of the body.

Anterior

The front side of the body.

Posterior

The back side of the body.

Superior

Towards the head.

Inferior

Towards the feet.

Cranial (Directional)

Towards the head.

Caudal

Towards the tail.

Superficial

Closer to the surface of the body.

Deep

Farther from the surface of the body.

Plantar

Refers to the bottom of the foot.

Dorsal (Foot)

Refers to the top of the foot.

Palmar

Refers to the palm side of the hand.

Dorsal (Hand)

Refers to the back of the hand.

Ipsilateral

On the same side of the body.

Contralateral

On the opposite side of the body.

Varus

A condition where the distal segment deviates toward the midline.

Valgus

A condition where the distal segment deviates away from the midline.

Sagittal Plane

Divides the body into left and right halves.

Frontal Plane

Divides the body into front and back halves.

Transverse Plane

Divides the body into top and bottom halves.

Flexion

A movement that decreases the angle between body parts.

Extension

A movement that increases the angle between body parts.

Circumduction

A circular movement that combines flexion, extension, abduction, and adduction.