Glossary 597
paravertebral ganglia (pair-a-VER-the-bral GAYNG-
glee-a) mass of nerve cell bodies close to the
spinal cord
parietal bones (pah-RIGH-eh-tal) bones that form the
majority of the top and sides of the skull
parietal layer (pah-RIGH-eh-tal) membrane lining the
interior of each body cavity
parietal lobes (pah-RIGH-eh-tal) sections of the brain
located behind the frontal lobes; integrate sensory
information from the skin, internal organs, muscles, and
joints
parietal pleura (pah-RIGH-eh-tal) the membrane that
lines the thoracic wall and diaphragm
Parkinson’s disease a chronic nervous system disease
characterized by a slowly spreading tremor, muscular
weakness, and rigidity
partial-thickness burns see fi rst- and second-degree
burns
parturition childbirth
passive immunity immunity that comes from antibodies
received from an outside source, such as breast milk
passive process a process that does not require the use
of muscles
passive transport type of membrane transport that does
not require energy
patella (pa-TEHL-a) kneecap
pathogens disease-causing agents
pectoral girdle (PEHK-toh-ral) bones surrounding
the shoulder, including the clavicle and scapula; the
shoulder girdle
pelvic cavity (PEHL-vik) internal opening that holds the
reproductive and excretory organs
pelvic girdle (PEHL-vik) bony encasement of the pelvic
region, formed by two large, strong coxal bones, (or hip
bones), and the sacrum
pelvis bones of the pelvic girdle and the coccyx at the
base of the spine
penis the reproductive organ that delivers sperm to the
female reproductive tract
pennate a type of muscle fi ber arrangement in which
each fi ber attaches obliquely to a central tendon
peptic ulcer a break in the protective lining of the
stomach, duodenum, or lower esophagus that is caused
by Helicobacter pylori
peptide bond the chemical bond that links two
amino acids by connecting the amino group of one
amino acid to the acid group of another
perforated septum a condition that causes one or more
holes to develop in the septum
perforating (Volkmann’s) canals large canals that
connect the Haversian canals
perforins (PER-for-ins) proteins made and released by a
T lymphocyte that join together to form a lethal pore in a
target cell (similar to membrane attack complex)
pericarditis (PER-i-kahr-DIGH-tis) infl ammation of the
pericardial sac that surrounds the heart
pericardium (PER-i-KAR-dee-um) the membrane that
surrounds the heart
perilymph (PER-i-limf) a clear fl uid that fi lls the bony
labyrinth
perimetrium (per-i-MEE-tree-um) the thin, membranous
outer layer of the uterine wall
perimysium (PER-i-MIZ-ee-um) connective tissue sheath
that envelops each primary bundle of muscle fi bers
perineurium (PER-i-NOO-ree-um) a protective sheath
that surrounds a bundle of nerve fi bers
periodontal disease (PER-ee-oh-DAHN-tal) disease
that affects the supporting structure of the teeth and the
gums
periodontal ligament (PER-ee-oh-DAHN-tal) the fi brous
connective tissue that covers the base of a tooth and
holds it in place in the jawbone
periosteum (PER-ee-AHS-tee-um) fi brous connective
tissue membrane that surrounds and protects the shaft
(diaphysis) of long bones
peripheral chemoreceptors sensory receptor cells
located in the aortic arch and carotid arteries that are
sensitive to changes in blood oxygen level
peripheral nervous system (PNS) all parts of the
nervous system external to the brain and spinal cord
peripheral neuropathy (noo-RAHP-a-thee) a disease
or degenerative state of the peripheral nerves often
associated with diabetes mellitus; marked by muscle
weakness and atrophy, pain, and numbness
peripheral vascular disease (PAD) condition caused by
a narrowing of the arteries in the legs
peristalsis (PER-i-STAHL-sis) a wave of symmetrical
squeezing of the digestive tract walls that occurs during
digestion
peritoneal cavity (PER-i-toh-NEE-al) the “empty space”
between the parietal and visceral peritoneum
peritoneal dialysis a renal dialysis method that uses
the patient’s peritoneum to fi lter fl uids and dissolved
substances from the blood
peritoneum (PER-i-toh-NEE-um) the membrane that
lines the abdominal cavity
peritonitis (PER-i-toh-NIGH-tis) infl ammation of the
peritoneum, the membrane lining the inner wall of the
abdomen and covering the abdominal organs
peritubular capillaries (per-i-TOO-byuh-lar) capillaries
that surround the proximal and distal convoluted tubules
pernicious anemia a severe anemia caused by the
inability of the intestines to absorb vitamin B12, which
is essential for the formation of red blood cells; usually
develops in older adults
Peyer’s patches clusters of mucosa-associated
lymphatic tissue (MALT) in the small intestine
pH a measure of the acidity or alkalinity of a solution
phagocytes (FAG-oh-sights) specialized white blood cells
that engulf and consume bacteria, foreign material, and
debris; distributed throughout the dermis
phagocytosis the process by which a cell engulfs and
destroys foreign matter and cellular debris
phalanges (fa-LAN-jeez) bones of the fi ngers
pharyngeal tonsil (fa-RIN-jee-al) lymphatic tissue that lies
at the back of the nasopharynx, the part of the throat above
the palate, and opens into the nasal cavity; the adenoid
pharyngitis (FAIR-in-JIGH-tis) infl ammation of the
pharynx, or throat
pharynx (FAIR-ingks) the muscular passageway that
extends from the nasal cavity to the mouth and connects
to the esophagus; the throat
pheochromocytoma (FEE-oh-KROH-moh-sigh-TOH-ma)
a tumor on the adrenal medulla, which causes
hypersecretion of epinephrine and norepinephrine
phlebotomy (fl eh-BAHT-oh-mee) the drawing of blood; a
standard treatment for polycythemia
phospholipids a lipid containing phosphate group
phototherapy a medical treatment in which the skin is
carefully exposed to ultraviolet light; light therapy
physiology (FIZ-ee-AHL-oh-jee) the study of how living
things function or work