584 Introduction to Anatomy and Physiology
class II MHC proteins major histocompatibility complex
proteins that are found only on the surfaces of certain
immune system cells
classical pathway a mode of complement system
activation in which a circulating complement protein
recognizes an antibody bound to foreign material.
Compare alternative pathway
clavicle doubly curved long bone that forms part of the
shoulder girdle; the collarbone
cleft palate a condition that occurs when the parts of the
palate do not completely fuse together during a fetus’
development in the womb
clitoris (KLIT-or-is) a cylindrical body of erectile tissue
that lies at the anterior end of the vulva
clonal selection repeated division of a lymphocyte that
produces many exact genetic copies (clones) of itself
clone cell or organism that is a genetic copy of an original
cell or organism
coagulation (KOH-ah-yoo-LAY-shun) the process by
which the enzyme thrombin and the protein fi brinogen fi
combine to form fi brin, a fi ber that weaves around the
platelet plug to form a blood clot; takes between 2 and 15
minutes to complete
coccyx (KAHK-siks) 4 fused vertebrae at the base of the
spine forming the tailbone
cochlea (KAHK-lee-a) a snail-shaped structure in the
inner ear that enables one to hear
cochlear duct (KAHK-lee-ar) the portion of the
membranous labyrinth inside the cochlea
codon (KOH-dahn) a set of three bases in DNA or RNA
that codes for one amino acid
coenzymes (koh-EHN-zighmz) molecules that are
necessary for the action of enzymes
collagen a protein found in skin that provides toughness
and binds with water molecules to keep the inner skin moist
collagen fibers fi fi bers of the cytoskeleton that are strong
and resistant to stretching
collecting duct a tube that collects urine from several
nephrons and carries it to the renal pelvis; urine can
become much more concentrated as it fl ows through the
collecting duct
collecting vessels a collection of lymphatic capillaries
colon longest segment of the large intestine
color blindness an inherited condition that affects
the cone cells on the retina and impairs the ability to
distinguish colors
columnar epithelia tall and skinny epithelia
combined loading the simultaneous action of two or
more types of forces
common warts warts that typically appear on the hands
or fi ngers and disappear without treatment
complement proteins proteins in the blood that work
with immune system cells and antibodies to defend the
body against infection
complement system a system of more than 30 proteins
that circulate in the blood plasma through the body
and work together to destroy foreign substances;
complements, or balances out, the specific and fi
nonspecifi c defense systems of the body
complex carbohydrate a long chain of simple sugars
joined together
compression a squeezing force that creates
compression in the structure to which it is applied
compressive strength the ability of a material to
withstand compression (inward-pressing force) without
buckling
concentric (kun-SEHN-trik) a type of contraction that
causes shortening of a muscle
conchae (KAHN-kee) three uneven, scroll-like
nasal bones that extend down through the nasal cavity;
these bones are divided into the superior, middle, and
inferior conchae
conducting zone the zone from the mouth or nose to the
terminal bronchioles
conduction the process of conveying or transmitting
types of energy, such as electrical impulses
conductivity the ability of a neuron to transmit a nerve
impulse
condyloid joint (KAHN-di-loyd) type of diarthrosis in
which one articulating bone surface is an oval, convex
shape, and the other is a reciprocally shaped concave
surface
cones sensory cells in the retina that are sensitive to
bright light and provide color vision
conjunctiva (KAHN-junk-TIGH-va) a delicate external
membrane that covers the exposed eyeball and lines the
eyelid
conjunctivitis (kahn-JUNK-ti-VIGH-tis) a highly
contagious inflammation of the conjunctiva; fl pink eye
connective tissue supporting tissue, which consists
mainly of an extracellular matrix
connective tissue proper a classifi cation of tissue that
includes loose and dense subtypes
constipation condition characterized by difficulty in
defecating
contractility the ability to contract or shorten
control center system that receives and analyzes
information from sensory receptors, then sends
a command stimulus to an effector to maintain
homeostasis
contusion the bruises or bleeding within a muscle that
result from an impact
convolutions the term used to describe the pattern of
gyri and the sulci that appear on the outer surface of the
brain
Cooley’s anemia a condition that affects the body’s
ability to produce fully developed hemoglobin and
red blood cells; thalassemia major
coracoid process (KOR-a-koyd) bony projection on the
posterior side of the scapula that serves as a site of
muscle attachments
cornea a transparent tissue over the anterior center of
the eye
coronary artery disease a narrowing of one or more of
the coronary arteries due to a buildup of plaque in the
artery; coronary heart disease
coronary heart disease see coronary artery disease
coronary sinus large venous channel between the left
atrium and left ventricle, on the posterior side of the heart
that empties into the right atrium at the junction of the
four chambers
corpora cavernosa (singular corpus cavernosum) one
type of erectile tissue
corpus spongiosum (spun-jee-OH-sum) one type of
erectile tissue
cortex outer portion of an organ, for example the outer
portion of a lymph node
cortical bone (KOR-ti-kal) dense, solid bone that covers
the outer surface of all bones and is the main form of
bone tissue in the long bones
cortical nephrons nephrons with short nephron loops
that penetrate only slightly into the renal medulla