Chapter 1: The Human Body

Need for Terminology

Communicate accurately with others in class and profession.

Anatomy

The study of the structure of the body.

Gross Anatomy

Anatomy visible to the naked eye.

Regional Anatomy

Study of specific regions, e.g., the left leg.

Systemic Anatomy

Study of specific systems, e.g., the cardiovascular system.

Microscopic Anatomy

Requires a microscope for study.

Cytology

The study of cells.

Histology

The study of tissues.

Developmental Anatomy

Changes in anatomy throughout the lifespan.

Physiology

The study of how and why the body functions.

Types of Physiology

Includes cellular level and organ system level.

Body's Organization

Levels include chemical, cellular, tissue, organ, organ systems, and organism.

Rule of Threes for Survival

Three minutes without oxygen, three hours without shelter, three days without water, three weeks without food.

Homeostasis

Relatively stable internal conditions of the body.

Nervous System

Controls homeostasis through electrical impulses and reflexes.

Endocrine System

Controls homeostasis through bloodborne hormones.

Negative Feedback Mechanism

Mechanism that counteracts initial changes to maintain homeostasis.

Positive Feedback Mechanism

Mechanism that amplifies initial changes, used in infrequent events.

Anatomical Position

Body erect, feet apart, palms forward, thumbs away from body.

Superior (Cranial)

Toward the head or upper part of the body.

Inferior (Caudal)

Away from the head or lower part of the body.

Anterior (Ventral)

Toward the front of the body.

Posterior (Dorsal)

Toward the back of the body.

Medial

Toward the midline of the body.

Lateral

Away from the midline of the body.

Proximal

Closer to the origin of a body part.

Distal

Farther from the origin of a body part.

Superficial (External)

Toward the body surface.

Deep (Internal)

Away from the body surface.

Divisions of the Body

Axial (head, neck, trunk) and Appendicular (limbs).

Body Planes

Methods to view or study the body.

Sagittal Plane

Sideways view of the body.

Midsagittal Plane

Cut made perfectly on the midline.

Frontal Plane

Divides body into anterior and posterior parts.

Transverse Plane

Divides body into superior and inferior parts.

Body Cavities

Internal organs lie in membrane-lined cavities.

Dorsal Body Cavity

Houses and protects the central nervous system.

Ventral Body Cavity

Houses visceral organs, divided by the diaphragm.

Thoracic Cavity

Contains pleural and pericardial cavities.

Abdominopelvic Cavity

Contains abdominal and pelvic organs.

Serous Membrane

Double-layered membrane covering organs.

Parietal Membrane

Covers the cavity walls.

Visceral Membrane

Covers the organs.

Serous Fluid

Allows organs to slide without friction across cavity walls.