Te number of protons in an atom.
Te one- or two-letter symbol used to indicate an ele-
ment; usually the ﬁrst letter(s) of the element’s name.
Te average of the mass numbers of all the isotopes of an
ATP (adenosine triphosphate)
fāt) Organic mol-
ecule that stores and releases chemical energy for use in body cells.
tre-ah) Te two superior receiving chambers of the heart.
Atrial natriuretic peptide (ANP)
ik) A hormone
released by certain cells of the heart atria that reduces blood pressure and
blood volume by inhibiting nearly all events that promote vasoconstric-
tion and Na
and water retention.
Atrioventricular (AV) bundle
kyoo-ler) Bundle of spe-
cialized ﬁbers that conduct impulses from the AV node to the right and
leF ventricles; also called bundle of His.
Atrioventricular (AV) node
Specialized mass of conducting cells lo-
cated at the atrioventricular junction in the heart.
Atrioventricular (AV) valve
Valve that prevents backﬂow into the
atrium when the connected ventricle is contracting.
ro-fe) Reduction in size or wasting away of an organ or cell
resulting from disease or lack of use.
sih-kulz) Te three tiny bones serving as transmit-
ters of vibrations and located within the middle ear: the malleus, incus,
Production of antibodies or eﬀector ± cells that attack a
person’s own tissue.
ĭ-sis) Process of autodigestion (self-digestion) of cells,
especially dead or degenerate cells.
Collection of sympathetic or parasympathetic
postganglionic neuronal cell bodies.
Autonomic nervous system (ANS)
Eﬀerent division of the peripheral
nervous system that innervates cardiac and smooth muscles and glands;
also called the involuntary or visceral motor system.
Autonomic (visceral) reﬂexes
Reﬂexes that activate smooth or cardiac
muscle and/or glands.
Te automatic local adjustment of blood ﬂow to a par-
ticular body area in response to its current requirements.
Chromosomes number 1 to 22; do not include the sex
rōz) Te number of molecules in one
mole of any substance, 6.02
Relating to the head, neck, and trunk; one of the two major divi-
sions of the body.
ah) Te plasma membrane of an axon.
Neuron process that carries impulses away from the nerve cell
body; eﬀerent process; the conducting portion of a nerve cell.
Axon terminals (terminal boutons)
Te bulbous distal endings of the
terminal branches of an axon.
Also called B lymphocytes; oversee humoral immunity; their de-
scendants diﬀerentiate into antibody-producing plasma cells.
tor) A sensory nerve ending in the wall of
the carotid sinus or aortic arch sensitive to vessel stretching.
sal) An organelle structurally identical to a centriole and
forming the base of a cilium or ﬂagellum.
Apocrine sweat gland
o-krin) Te less numerous type of sweat gland;
produces a secretion containing water, salts, proteins, and fatty acids.
ō-en-zīm) Te protein portion of an enzyme.
sis) ²ibrous or membranous sheet connecting
a muscle and the part it moves.
A process of controlled cellular suicide; eliminates cells that
are unneeded, stressed, or aged.
tis) Inﬂammation of the appendix (wormlike
sac attached to the cecum of the large intestine).
Relating to the limbs; one of the two major divisions of
Growth accomplished by the addition of new lay-
ers onto those previously formed.
ins) ±ransmembrane proteins that form water
kwe-us) Watery ﬂuid in the anterior segment of the eye.
noid) Weblike; speciﬁcally, the weblike arachnoid
mater, the middle layer of the three meninges.
o-lah) Circular, pigmented area surrounding the nipple;
any small space in a tissue.
Areolar connective tissue
A type of loose connective tissue.
li) ±iny, smooth muscles attached to hair
follicles; contraction causes the hair to stand upright.
me-ah) Irregular heart rhythm, oFen caused by de-
fects in the intrinsic conduction system.
Blood vessels that conduct blood away from the heart and into
e-ōl) A minute artery.
sis) Any of a number of prolifera-
tive and degenerative changes in the arteries leading to their decreased
Inﬂammation of the joints.
ik) Procedure enabling a surgeon
to repair the interior of a joint through a small incision.
Double-layered capsule composed of an outer ﬁbrous
layer lined by synovial membrane; encloses the joint cavity of a synovial
Hyaline cartilage covering bone ends at movable
Te junction of two or more bones.
²unctional areas of the cerebral cortex that act mainly
to integrate diverse information for purposeful action.
mah-tizm) A condition in which unequal curvatures
in diﬀerent parts of the cornea or lens of the eye lead to blurred vision.
tro-sīt) A type of CNS supporting cell; assists in exchanges
between blood capillaries and neurons.
tah-sis) Lung collapse.
sis) Changes in the walls of large
arteries consisting of lipid deposits on the artery walls; one form of
²orce that air exerts on the surface of the body
(760 mm Hg at sea level).
Smallest particle of an elemental substance that exhibits the prop-
erties of that element; composed of protons, neutrons, and electrons.