Anatomy and Physiology: Body Structures, Functions, and Body Cavities

Anatomy

Study of body structures and relationships to other parts.

Physiology

Study of how body parts function.

Complementarity of Structure and Function (form follows function)

Physical arrangements of body parts determine capabilities and purpose.

Gross Anatomy

Study of body structures large enough to see without a microscope.

Microscopic Anatomy

Study of body structures with a microscope.

Cytology

Study of individual cells.

Histology

Study of tissues.

Cadaver

Dead human body, usually for dissection.

Homeostasis

Maintaining an internal environment that is within a range of stability and balance.

Negative Feedback Homeostasis

Counteracts a change (e.g., thermoregulation – sweating).

Positive Feedback Homeostasis

Exaggerates or enhances a change instead of opposing it (e.g., baby pushing cervix creates oxytocin that causes contractions until delivery ends pressure).

Anatomical Position

Standard human body reference — hands at sides, palms forward, feet together. Right and left are from the patient's perspective.

Supine

Lying face up (on spine).

Prone

Lying face down.

Sagittal Plane (median)

Cuts body into left and right portions.

Frontal Plane (coronal)

Cuts body into front and back portions.

Transverse Plane (horizontal)

Cuts body into upper and lower portions.

Quadrants

RUQ (Right Upper Quadrant), LUQ (Left Upper Quadrant), RLQ (Right Lower Quadrant), LLQ (Left Lower Quadrant).

Abdominopelvic Regions

Right hypochondriac, epigastric, left hypochondriac, right lumbar, umbilical, left lumbar, right iliac, hypogastric, left iliac.

Femoral

Thigh

Gluteal

Butt

Lumbar

Lower back, left and right of vertebral

Occipital

Lower back of head

Pollex

Thumb

Palmar

Palm

Cervical

Neck

Orbital

Eye socket

Axillary

Armpit

Antecubital

Front of elbow (anterior)

Carpal

Wrist

Cranial

Toward the head

Caudal

Toward the tail

Anterior (ventral)

Front

Posterior (dorsal)

Back

Superior

Above

Inferior

Below

Proximal

Closer to the trunk

Distal

Farther from the trunk

Medial

Toward the midline

Lateral

Toward the side

Body Cavities

Fluid spaces in the body containing organs.

Viscera

Internal organs within cavities.

Dorsal Body Cavity

Posterior cavity containing the cranial and vertebral cavities (Central Nervous System).

Cranial Cavity

Contains the brain.

Vertebral Cavity

Contains the spinal cord.

Ventral Body Cavity

Anterior cavity divided by the diaphragm into thoracic and abdominopelvic cavities.

Thoracic Cavity

Located above the diaphragm; contains the heart and lungs.

Pleural Cavity

Contains the lungs.

Superior Mediastinum

Upper thorax (mediastinum).

Pericardial Cavity (within mediastinum)

Contains the heart.

Abdominopelvic Cavity

Located below the diaphragm; contains abdominal and pelvic cavities.

Abdominal Cavity

Abdomen; contains digestive organs.

Pelvic Cavity

Pelvis; contains urinary, reproductive, and digestive organs.