3 - The Remarkable Body Flashcards
any of a great number of working proteins
that speed up a specific chemical reaction,
such as breaking the bonds of a nutrient, without
undergoing change themselves.
enzyme
an inborn error of metabolism that interferes with the body’s
handling of the amino acid phenylalanine, with
potentially serious consequences to the brain
and nervous system in infancy and childhood.
phenylketonuria (PKU)
a genetic variation present from birth that may result in
disease.
inborn error of metabolism
cells that specialize in the storage of fat and form the fat tissue.________ also produce fat-metabolizing enzymes; they also produce hormones involved in appetite and
energy balance
Fat cells
systems of cells working together
to perform specialized tasks. Examples are
muscles, nerves, blood, and bone.
tissues
discrete structural units made of tissues
that perform specific jobs. Examples are the
heart, liver, and brain.
organs
a group of related organs that work together to perform a function. Examples are the circulatory system, respiratory system, and nervous system.
body system
the fluid of the cardiovascular system;
composed of water, red and white blood cells,
other formed particles, nutrients, oxygen, and
other constituents. lymph (LIMF) the fluid that moves from the bloodstream into tissue spaces and then travels
in its own vessels, which eventually drain back
into the bloodstream (see Figure 3–6).
blood
blood vessels that carry blood containing
fresh oxygen supplies from the heart to the
tissues
arteries
blood vessels that carry blood, with the
carbon dioxide it has collected, from the tissues
back to the heart
veins
minute, weblike blood vessels that
connect arteries to veins and permit transfer
of materials between blood and tissues
plasma the cell-free fluid part of blood and
lymph.
capillaries
a pair of organs that filter wastes from
the blood, make urine, and release it to the
bladder for excretion from the body.
kidneys
the body’s long, tubular organ of
digestion and the site of nutrient absorption.
liver a large, lobed organ that lies just under
the ribs. It filters the blood, removes and
processes nutrients, manufactures materials for
export to other parts of the body, and destroys
toxins or stores them to keep them out of the
circulatory system.
intestine
the body’s organs of gas exchange. Blood
circulating through the lungs releases its carbon
dioxide and picks up fresh oxygen to carry to
the tissues.
lungs
fluid residing inside the
cells that provides the medium for cellular
reactions.
intracellular fluid
fluid residing outside the cells that transports materials to and from the cells.
extracellular fluid
chemicals that are secreted by
glands into the blood in response to conditions
in the body that require regulation. These
chemicals serve as messengers, acting on other
organs to maintain constant conditions.
pancreas an organ with two main functions.
One is an endocrine function—the making of
hormones such as insulin, which it releases
directly into the blood (endo means “into” the
blood). The other is an exocrine function—the
making of digestive enzymes, which it releases
through a duct into the small intestine to assist
in digestion (exo means “out” into a body cavity
or onto the skin surface).
hormones
a hormone from the pancreas that
helps glucose enter cells from the blood
insulin
a hormone from the pancreas that
stimulates the liver to release glucose into the
bloodstream.
glucagon
the outermost layer of something. The
brain’s cortex is the part of the brain where
conscious thought takes place.
cortex
a part of the brain that senses a variety of conditions
in the blood, such as temperature, glucose
content, salt content, and others. It signals other
parts of the brain or body to adjust those conditions
when necessary.
hypothalamus (high-poh-THAL-uh-mus)
reaction the body’s instinctive hormone- and nerve-mediated reaction to danger. Also known as the stress response.
fight-or-flight
the major hormone that elicits the stress response.
epinephrine (EP-ih-NEFF-rin)
a compound related to epinephrine that helps to
elicit the stress response.
norepinephrine (NOR-EP-ih-NEFF-rin)
the sum of all physical and chemical
changes taking place in living cells; includes
all reactions by which the body obtains and
spends the energy from food.
metabolism
chemicals that are released at the end of a nerve cell when a nerve impulse arrives there. They diffuse across the gap to the next cell and alter the membrane of that second cell to either inhibit or excite it.
neurotransmitters
bacteria, viruses, or other organisms
invisible to the naked eye, some of which cause
diseases. Also called microorganisms.
microbes
a system of tissues and organs that defend the body against antigens, foreign materials that have penetrated the skin or body linings.
immune system
white blood cells that participate in the immune response;
B-cells and T-cells.
lymphocytes (LIM-foh-sites)
white blood cells that can ingest and destroy antigens. The process by which phagocytes engulf materials
is called phagocytosis. The Greek word phagein
means “to eat.”
phagocytes (FAG-oh-sites)
a microbe or substance that is foreign to the body.
antigen
lymphocytes that attack antigens. The _____ are stored and matured in the thymus gland of the neck
T-cells
lymphocytes that produce antibodies.
B-cells
proteins, made by cells of the immune system, that are expressly designed to combine with and inactivate specific antigens.
antibodies
the immune system’s response to cellular injury characterized by an increase in white blood cells, redness, heat, pain, and swelling.
________________ plays a role in many chronic
diseases.
inflammation
the body system composed of organs that break down complex food particles into smaller, absorbable products.
digestive system
to break molecules into smaller molecules;
a main function of the digestive tract
with respect to food.
digest
to take in, as nutrients are taken into the intestinal cells after digestion; the main function of the digestive tract with respect to nutrients.
absorb
The (A)__________ and (B)__________ are names
for the tubular organs that extend from the mouth to the anus. The whole system, including the pancreas, liver, and gallbladder, is sometimes called the gastrointestinal, or GI, system.
A. digestive tract
B. alimentary canal
the wavelike muscular squeezing of the esophagus, stomach, and small intestine that pushes their contents
along.
peristalsis (perri-STALL-sis)
a muscular, elastic, pouchlike organ
of the digestive tract that grinds and churns
swallowed food and mixes it with acid and
enzymes, forming chyme.
stomach
a circular muscle surrounding, and able to close, a body opening. chyme (KIME) the fluid resulting from the
actions of the stomach upon a meal.
sphincter (SFINK-ter)
the circular muscle of the lower stomach that regulates the
flow of partly digested food into the small intestine.
Also called pyloric sphincter.
pyloric (pye-LORE-ick) valve
the 20-foot length of small-diameter intestine, below the stomach and above the large intestine, that is the major site of digestion of food and absorption of nutrients.
small intestine
the portion of the intestine that
completes the absorption process.
large intestine
the large intestine.
colon
waste material remaining after digestion
and absorption are complete; eventually
discharged from the body.
feces
the digestive secretion of the
stomach.
gastric juice
a strong corrosive acid of
hydrogen and chloride atoms, produced by the
stomach to assist in digestion.
hydrochloric acid
a measure of acidity on a point scale.
pH
a slippery coating of the
digestive tract lining (and other body linings)
that protects the cells from exposure to digestive
juices (and other destructive agents). The adjective
form is mucous (same pronunciation). The
digestive tract lining is a mucous membrane.
mucus (MYOO-cus)
A solution with a pH of 1 is a A)_______; a solution
with a pH of 7 is B)_______; a solution with a
pH of 14 is a C)_______strong base.
A) strong acid
B) neutral
C) strong base
a suffix meaning enzyme. Categories of digestive and other enzymes and individual enzyme names often contain this suffix.
-ase (ACE)
any of a number of enzymes that break the chemical bonds of carbohydrates.
carbohydrase (car-boh-HIGHdrace)
any of a number of enzymes that break the chemical
bonds of fats (lipids).
lipase (LYE-pace)
any of a number of enzymes that break chemical bonds of proteins
protease (PRO-tee-ace)
a cholesterol-containing digestive fluid
made by the liver, stored in the gallbladder, and
released into the small intestine when needed. It
emulsifies fats and oils to ready them for enzymatic
digestion
bile
a compound with both water-soluble and fat-soluble portions that can attract fats and oils into water, combining
them.
emulsifier (ee-MULL-sih-fire)
fluid secreted by the pancreas that contains both enzymes to digest carbohydrates, fats, and proteins and sodium
bicarbonate, a neutralizing agent.
pancreatic juice
a common alkaline chemical; a
secretion of the pancreas; also the active ingredient
of baking soda.
bicarbonate
fingerlike projections of the sheets of cells lining the intestinal tract. The ____ make the surface area much
greater than it would otherwise be.
villi (VILL-ee, VILL-eye)
tiny, hairlike projections on each cell
of every villus that greatly expand the surface
area available to trap nutrient particles and
absorb them into the cells
microvilli (MY-croh-VILL-ee, MY-croh-
VILL-eye)
spasms of both the vocal cords and
the diaphragm, causing periodic, audible, short,
inhaled coughs. Can be caused by irritation of
the diaphragm, indigestion, or other causes.
_____usually resolve in a few minutes but
can have serious effects if prolonged. Breathing
into a paper bag (inhaling carbon dioxide) or
dissolving a teaspoon of sugar in the mouth may
stop them.
hiccups
a burning sensation in the chest
(in the area of the heart) caused by backflow of
stomach acid into the esophagus.
heartburn
medications that react directly and
immediately with the acid of the stomach,
neutralizing it. Antacids are most suitable for
treating occasional heartburn.
antacids
prescription and over-thecounter drugs that reduce the acid output of the stomach; effective for treating severe, persistent forms of heartburn but not for neutralizing acid
already present. Side effects are frequent and
include diarrhea, other gastrointestinal complaints,
and reduction of the stomach’s capacity to destroy alcohol, thereby producing higher-than- expected blood alcohol levels from each drink Also called acid controllers.
acid reducers
swollen, hardened (varicose) veins in the rectum,
usually caused by the pressure resulting from
[ Anti-inflammatory drugs such as aspirin, ibuprofen, and naproxen sodium. constipation.
hemorrhoids (HEM-or-oids)
frequent, watery bowel movements usually caused by diet, stress, or irritation of the colon. Severe, prolonged diarrhea robs the body of fluid and certain minerals, causing dehydration and imbalances that can be dangerous if left untreated.
diarrhea
infrequent, difficult bowel movements often caused by diet, inactivity, dehydration, or medication.
constipation
an erosion in the topmost, and sometimes
underlying, layers of cells that form a lining.
______of the digestive tract commonly form in the
esophagus, stomach, or upper small intestine.
hernia a protrusion of an organ or part of an
organ through the wall of the body chamber that
normally contains the organ. An example is a
hiatal (high-AY-tal) hernia, in which part of the
stomach protrudes up through the diaphragm
into the chest cavity, which contains the esophagus,
heart, and lungs.
ulcer
intermittent disturbance of bowel function, especially
diarrhea or alternating diarrhea and constipation,
often with abdominal cramping or bloating;
managed with diet, physical activity, or relief
from psychological stress. The cause is uncertain,
but IBS does not permanently harm the
intestines nor lead to serious diseases.
irritable bowel syndrome (IBS)
a severe and chronic splashing of stomach acid and enzymes into the esophagus, throat, mouth, or airway that causes injury to those organs. Untreated GERD
may increase the risk of esophageal cancer;
treatment may require surgery or management
with medication.
gastroesophageal (GAS-tro-eh-SOFF-ahjeel) reflux disease (GERD)
a storage form of carbohydrate energy (glucose)
glycogen
the working units in the kidneys, consisting of intermeshed blood vessels and tubules.
nephrons (NEFF-rons)
the sac that holds urine until time for
elimination.
bladder
