Fundamentals of Anatomy and Physiology

Glossary

A^
A bands the dark, thick bands of the protein myosin in mus-
cle cells^
Abdominal aorta the part of the aorta located in the
abdomen
Abdominopelvic cavity second subdivision of the ventral
cav-ity that contains the kidneys, stomach, liver and
gallbladder, small and large intestines, spleen, pancreas, and
the ovaries and uterus (in women)^
Abducens nerve VI controls movement of the eyeball
Abduction movement of a bone or limb away from the mid-
line of the body^
Abductor digiti minimi muscle that abducts little toe
Abductor hallucis muscle that abducts, flexes great
toe Abductor pollicis muscle that abducts the thumb
ABO blood group one of the blood groups
Absorption the passage of digested food from the digestive
tract into the cardiovascular and lymphatic systems for dis-
tribution to the body’s cells^
Accessory nerve XI helps control swallowing and
movements^ of the head^
Acetabulum deep socket on the lateral side of the hipbone

just above the obturator foramen^
Acetaldehyde an intermediate product of fermentation
Acetic acid an intermediate product of the citric acid cycle
Acetylcholine neurotransmitter substance
Acetylcholinesterase an enzyme in the postsynaptic neuron
that breaks down acetylcholine^
Acetyl - CoA an intermediate product of the citric acid cycle
Acid a substance that dissociates and forms an excess of H

ions when dissolved in water^
Acidosis a condition caused by lowering of blood pH
Acid rain rain with a high acid concentration resulting from
pollutants emitted from cars and coal-fired power plants^
Acini exocrine glands of the pancreas
Acromegaly overdevelopment of bones of hands, feet, face,
and jaw^
Acromial process bony prominence on the scapula
Acrosome contains enzymes that aid the sperm cell in pen-
etrating the ovum^
Actin thin filaments of protein in a muscle cell
Action potential when a muscle generates its own impulse to
contract

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Active immunity a type of immunity acquired naturally when

exposed to a bacterium or virus or acquired artificially through

a vaccine^

Active transport mechanism requiring energy by which cells

acquire materials against a concentration gradient^

Adam’s apple thyroid cartilage

Addison’s disease condition in which the adrenal cortex

fails^ to produce enough hormones^

Adduction movement of a bone or limb toward the midline of

the body^

Adductor pollicis muscle that adducts the

thumb Adenine a purine nitrogen base

Adenoids pharyngeal tonsils

Adenosine triphosphate (ATP) high-energy fuel molecule

the^ cell needs to function^

Adipose loose connective tissue full of fat cells

Adipose capsule second layer of tissue that surrounds the

kidney

Adrenal cortex outermost part of the adrenal gland

Adrenal glands small glands found on top of each kidney;

suprarenal glands^

Adrenal medulla inner part of the adrenal gland

Adrenaline a neurotransmitter also called epinephrine used by

the autonomic nervous system; a hormone^

Adrenocorticotropic hormone (ACTH) stimulates the

adrenal^ cortex to secrete the hormone cortisol^

Adrenogenital syndrome excessive secretion of androgens

producing male characteristics in females and an early

enlarged- penis in young males^

Adventitia the outermost layer of the wall of the alimentary

canal

Aerobic requires oxygen

Afferent arteriole takes blood from the renal artery to

­Bowman’s glomerular capsule^

Afferent lymphatic vessels lymphatic vessels that enter the

lymph nodes at various sites^

Afferent peripheral system consists of afferent or sensory

neurons that convey information from receptors in the

-periphery of the body to the brain and spinal cord^

Agglutination clumping of red blood cells

Agonists muscles performing the actual movement

AIDS acquired immunodeficiency syndrome

Albinism the absence of skin color