G-1
Glossary
Pronunciation Key
9
5
Primary accent
0
5
Secondary accent
Pronounce:
a, fa, āt
as in
fate
o, no, ōt
as in
note
ă, hă, at
 
hat
ŏ, frŏ, og
 
frog
ah
 
father
oo
 
soon
ar
 
tar
or
 
for
e, stre, ēt
 
street
ow
 
plow
ĕ, hĕ, en
 
hen
oy
 
boy
er
 
her
sh
 
she
ew
 
new
u, mu, ūt  
mute
g
 
go
ŭ, sŭ, un
 
sun
i, bi, īt
 
bite
z
 
zebra
ĭ, hĭ, im
 
him
zh
 
measure
ng
 
ring
 
 
 
Abduct
(ab-dukt
9
) To move away from the midline of the body.
Absolute refractory period
Period following stimulation during which
no additional action potential can be evoked.
Absorption
Process by which the products of digestion pass through the
alimentary tube mucosa into the blood or lymph.
Accessory digestive organs
Organs that contribute to the digestive pro-
cess but are not part of the alimentary canal; include the tongue, teeth,
salivary glands, pancreas, liver.
Accommodation
±e process of increasing the refractive power of the
lens of the eye; focusing.
Acetabulum
(as
0
ĕ-tab
9
u-lum) Cuplike cavity on lateral surface of the hip
bone that receives the femur.
Acetylcholine (ACh)
(as
0
ĕ-til-ko
9
lēn) Chemical transmitter substance
released by some nerve endings.
Acetylcholinesterase (AChE)
(as
0
ĕ-til-ko
0
lin-es
9
ter-ās) Enzyme present
at the neuromuscular junction and synapses that degrades acetylcholine
and terminates its action.
Achilles tendon
See
Calcaneal tendon.
Acid
A substance that releases hydrogen ions when in solution (compare
with Base); a proton donor.
Acid-base balance
Situation in which the pH of the blood is maintained
between 7.35 and 7.45.
Acidosis
(as
0
ĭ-do
9
sis) State of abnormally high hydrogen ion concentra-
tion in the extracellular fluid.
Actin
(ak
9
tin) A contractile protein of muscle.
Action potential
A large transient depolarization event, including polar-
ity reversal, that is conducted along the membrane of a muscle cell or a
nerve fiber.
Activation energy
±e amount of energy required to push a reactant to
the level necessary for action.
Active immunity
Immunity produced by an encounter with an antigen;
provides immunological memory.
Active site
Region on the surface of a functional (globular) protein
where it binds and interacts chemically with other molecules of comple-
mentary shape and charge.
Active (transport) processes
(1) Membrane transport processes for
which ATP is required, e.g., solute pumping and endocytosis. (2) “Active
transport” also refers specifically to solute pumping.
Adaptation
(1) Any change in structure or response to suit a new environ-
ment; (2) decline in the transmission of a sensory nerve when a receptor is
stimulated continuously and without change in stimulus strength.
Adduct
(a-dukt
9
) To move toward the midline of the body.
Adenine (A)
(ad
9
ĕ-nēn) One of the two major purines found in both
RNA and DNA; also found in various free nucleotides of importance to
the body, such as ATP.
Adenohypophysis
(ad
0
ĕ-no-hi-pof
9
ĭ-sis) Anterior pituitary; the glandu-
lar part of the pituitary gland.
Adenoids
(ad
9
en-noids) Pharyngeal tonsil.
Adenosine triphosphate (ATP)
(ah-den
9
o-sēn tri
0
fos
9
fāt) Organic mol-
ecule that stores and releases chemical energy for use in body cells.
Adipocyte
(ad
9
ĭ-po-sīt) An adipose, or fat, cell.
Adipose tissue
(ad
9
ĭ-pōs) Areolar connective tissue modified to store
nutrients; a connective tissue consisting chiefly of fat cells.
Adrenal glands
(uh-drē
9
nul) Hormone-producing glands located supe-
rior to the kidneys; each consists of medulla and cortex areas.
Adrenergic fibers
(ad
0
ren-er
9
jik) Nerve fibers that release norepineph-
rine.
Adrenocorticotropic hormone (ACTH)
(ah-dre
0
no-kor
0
tĭ-ko-trop
9
ik)
Anterior pituitary hormone that influences the activity of the adrenal
cortex.
Adventitia
(ad
0
ven-tish
9
e-ah) Outermost layer or covering of some organs.
Aerobic
(a
9
er-ōb
0
ik) Oxygen-requiring.
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