Human Anatomy and Physiology: Structural Organization, Homeostasis, and Terminology

Comprehensive vocabulary flashcards covering the structural organization levels, organ system functions, homeostatic control mechanisms, directional terminology, body planes, and cavities as presented in the lecture materials.

Chemical level

The simplest level of relevant structural organization where atoms combine to form molecules.

Cellular level

The level of structural organization where cells are made up of molecules.

Tissue level

The level of structural organization where tissues consist of similar types of cells.

Organ level

The level of structural organization where organs are made up of different types of tissues.

Organ system level

The level consisting of different organs that work together closely to perform a specific function.

Organismal level

The highest level of structural organization where the human organism is made up of many organ systems.

Interstitial fluid

The fluid through which nutrients and wastes pass between blood and cells.

Integumentary System

Forms the external body covering; protects deeper tissues from injury; synthesizes $Vitamin\,D$; houses cutaneous receptors and sweat/oil glands.

Skeletal System

Protects and supports body organs; provides a framework for muscle movement; forms blood cells within bones and stores minerals.

Muscular System

Allows manipulation of the environment, locomotion, and facial expression; maintains posture and produces heat.

Nervous System

The fast-acting control system of the body; responds to internal and external changes by activating appropriate muscles and glands.

Endocrine System

Glands secrete hormones that regulate processes such as growth, reproduction, and metabolism by body cells.

Cardiovascular System

Blood vessels transport blood carrying $O_2$, $CO_2$, nutrients, and wastes; the heart pumps the blood.

Lymphatic System/Immunity

Picks up fluid leaked from blood vessels and returns it to blood; disposes of debris; houses white blood cells (lymphocytes) involved in immunity.

Respiratory System

Keeps blood supplied with $O_2$ and removes $CO_2$; gaseous exchanges occur through the walls of the air sacs of the lungs.

Digestive System

Breaks down food into absorbable units that enter the blood; indigestible foodstuffs are eliminated as feces.

Urinary System

Eliminates nitrogenous wastes; regulates water, electrolyte, and acid-base balance of the blood.

Reproductive System

The overall function is production of offspring; includes testes/sperm in males and ovaries/eggs/fetus development sites in females.

Homeostatic Receptor

The element of a control system that detects a change or stimulus.

Afferent pathway

The route by which information from the receptor is sent to the control center.

Control Center

The element that determines the set point, analyzes input, and coordinates a response.

Efferent pathway

The route by which information from the control center is sent to the effector.

Effector

The component that provides the means for the control center's response to the stimulus.

Negative feedback mechanism

The response of the effector feeds back to reduce the effect of the stimulus, returning the variable to a homeostatic level (e.g., body temperature regulation).

Positive feedback mechanism

A mechanism where the response enhances or accelerates the original stimulus (e.g., formation of a platelet plug).

Superior (cranial)

Toward the head end or upper part of a structure or the body; above.

Inferior (caudal)

Away from the head end or toward the lower part of a structure or the body; below.

Ventral (anterior)

Toward or at the front of the body; in front of.

Dorsal (posterior)

Toward or at the back of the body; behind.

Medial

Toward or at the midline of the body; on the inner side of.

Lateral

Away from the midline of the body; on the outer side of.

Intermediate

Between a more medial and a more lateral structure.

Proximal

Closer to the origin of the body part or the point of attachment of a limb to the body trunk.

Distal

Farther from the origin of a body part or the point of attachment of a limb to the body trunk.

Superficial (external)

Toward or at the body surface.

Deep (internal)

Away from the body surface; more internal.

Frontal plane

A vertical plane that divides the body into anterior and posterior parts.

Transverse plane

A horizontal plane that divides the body into superior and inferior parts.

Median (midsagittal) plane

A vertical plane that divides the body into exactly right and left parts.

Dorsal body cavity

Composed of the Cranial cavity (containing the brain) and the Vertebral cavity (containing the spinal cord).

Ventral body cavity

Composed of the Thoracic cavity and the Abdominopelvic cavity.

Thoracic cavity

Contains the heart and lungs; further subdivided into the pleural cavities, superior mediastinum, and pericardial cavity.

Abdominopelvic cavity

Consists of the Abdominal cavity (stomach, intestines, liver, etc.) and the Pelvic cavity (bladder, reproductive organs, and rectum).

Parietal serosa

The part of the double-layered membrane (serosa) that lines the walls of the ventral body cavity.

Visceral serosa

The part of the double-layered membrane (serosa) that covers the external surface of organs within the ventral body cavity.

Epigastric region

The upper middle region of the nine abdominopelvic regions, located superior to the Umbilical region.

Hypogastric (pubic) region

The lower middle region of the nine abdominopelvic regions, located inferior to the Umbilical region.

Umbilical region

The centermost region of the nine abdominopelvic regions, surrounding the navel.