| solvent | A liquid substance in which other
substances dissolve.
|
 |
|
|
| intracellular fluid | Fluid contained within
a cell; it represents about two-thirds of all
body fluid.
|
|
|
|
| extracellular fluid | Fluid present outside the
cells; represents about one-third of all body
fluid.
|
|
|
|
| electrolytes | Substances that separate into
ions in water and, in turn, are able to conduct
an electrical current. These include sodium,
chloride, and potassium.
|
|
|
|
| osmosis | The passage of a solvent such as
water through a semipermeable membrane
from a less concentrated compartment to a
more concentrated compartment.
|
|
|
|
| urea | Nitrogen-containing waste product of
protein metabolism; major source of nitrogen
in the urine.
|
|
|
|
| amniotic fluid | Fluid contained in a sac
within the uterus. This fluid surrounds and
protects the fetus during development.
|
|
|
|
| antidiuretic hormone | A hormone that is
secreted by the pituitary gland and that acts
on the kidneys to decrease water excretion.
|
|
|
|
| aldosterone | A hormone produced by the
adrenal glands that acts on the kidneys to
conserve sodium (and therefore water).
|
|
|
|
| cofactor | A mineral or other substance that
binds to a specific region on a protein, such as
an enzyme, and is necessary for the protein’s
function.
|
|
|
|
| major mineral | A mineral vital to health that
is required in the diet in amounts greater than
100 milligrams per day.
|
|
|
|
| trace mineral | A mineral vital to health that
is required in the diet in amounts less than
100 milligrams per day.
|
|
|
|
| bioavailability | The degree to which an
ingested nutrient is absorbed and available
to the body.
|
|
|
|
| oxalic acid (oxalate) | An organic acid
found in spinach, rhubarb, and other leafy
green vegetables that can depress the
absorption of certain minerals present in the
food, such as calcium.
|
|
|
|
| phytic acid (phytate) | A constituent of
plant fibers that binds positive ions to its
multiple phosphate groups.
|
|
|
|
| diuretic | A substance that increases the flow
of urine.
|
|
|
|
| osteoporosis | Decreased bone mass related
to the effects of aging, genetic background
and poor diet in both genders, and hormonal
changes at menopause in women.
|
|
|
|
| tetany | A body condition marked by sharp
contraction of muscles and failure to relax
afterward; usually caused by abnormal
calcium metabolism.
|
|
|
|
| hemoglobin | The iron-containing part of the
red blood cell that carries oxygen to the cells
and some carbon dioxide away from the cells.
The heme iron portion is also responsible for
the red color of blood.
|
|
|
|
| myoglobin | Iron-containing protein that
binds oxygen in muscle tissue.
|
|
|
|
| heme iron | Iron provided from animal tissues
in the form of hemoglobin and myoglobin.
Approximately 40% of the iron in meat is
heme iron; it is readily absorbed.
|
|
|
|
| nonheme iron | Iron provided from plant
sources and animal tissues other than in
the forms of hemoglobin and myoglobin.
Nonheme iron is less efficiently absorbed
than heme iron; absorption is closely
dependent on body needs.
|
|
|
|
| hematocrit | The percentage of blood that is
made up of red blood cells.
|
|
|
|
| anemia | Generally refers to a decreased
oxygen-carrying capacity of the blood. This
can be caused by many factors, such as iron
deficiency or blood loss.
|
|
|
|
| hemochromatosis | A disorder of iron metabolism
characterized by increased iron absorption
and deposition in the liver and heart
tissue. This eventually poisons the cells in
those organs.
|
|
|
|
| goiter | An enlargement of the thyroid gland;
this is often caused by insufficient iodide in
the diet.
|
|
|
|
| cretinism | The stunting of body growth and
poor mental development in the offspring
that results from inadequate maternal intake
of iodide during pregnancy.
|
|
|
|
| mottling | The discoloration or marking of the
surface of teeth from fluorosis.
|
|
|
|
| cortical bone | Dense, compact bone that
comprises the outer surface and shafts of
bone; also called compact bone.
|
|
|
|
| trabecular bone | The spongy, inner matrix
of bone, found primarily in the spine, pelvis,
and ends of bones; also called spongy or
cancellous bone.
|
|
|
|
| bone mass | Total mineral substance (such as
calcium or phosphorus) in a cross section of
bone, generally expressed as grams per
centimeter of length.
|
|
|
|
| bone mineral density | Total mineral content
of bone at a specific bone site divided by the
width of the bone at that site, generally
expressed as grams per cubic centimeter.
|
|
|
|
| Dual energy X-ray absorptiometry (DEXA) bone scan | Method to measure
bone density that uses small amounts of X-ray
radiation. The ability of a bone to block the
path of the radiation is used as a measure of
bone density at that bone site.
|
|
|
|
| bisphosphonates | Compounds primarily
composed of carbon and phosphorus that
bind to bone mineral and in turn reduce bone
breakdown. Examples are alendronate
(Fosamax) and risedronate (Actonel).
|