Chapter 1 Flashcards
. is in constant motion throughout the body. It is transported rapidly in the circulating blood and then mixed between the blood and the tissue fluids by diffusion through the capillary walls.
extracellular fluid
are the ions and nutrients
needed by the cells to maintain cell life.
Extracellular fluid
also called the internal environment of the body, or the milieu intérieur,
Extracellular fluid
The extracellular fluid contains what?
large amounts of sodium
Chloride
bicarbonate ions
plus nutrients for the cells such as oxygen, glucose, fatty acids, and amino acids. And contains carbon dioxide
Intracellular fluid contains what?
Potassium
Magnesium
Phosphate ions
control cell function by determining which substances are synthesized within the cell—which structures,
which enzymes, which chemicals.
Genes
automatically controls the formation of another nucleic acid, RNA
.
DNA
spreads throughout the cell to control
the formation of a specific protein.
RNA
;The entire process, from transcription of the genetic code in the nucleus to translation of the RNA code and formation or proteins in the cell cytoplasm
.
Gene expression
promote all the oxidative reactions that supply energy to the cell, and they promote synthesis of all the cell chemicals, such as lipids, glycogen, and adenosine triphosphate (ATP).
enzymes
are too
large to readily pass through the capillaries.
Plasma protein molecules
are permeable
to most molecules in the plasma of the blood
walls of the capillaries
Where do the blood picks up oxygen
Alveoli
Membrane between alveoli and the lumen of the pulmonary capillaries.
O. 4 to 2.0 micrometers thick and oxygen rapidly diffuses by molecular motion through this membrane into the blood.
Alveolar membrane
Here different dissolved nutrients,
including carbohydrates, fatty acids, and amino acids, are
absorbed from the ingested food into the extracellular fluid of the blood.
Gastrointestinal tract
changes the chemical compositions of many of these substances from GI tract to more usable forms.
also eliminates certain waste products produced
in the body and toxic substances that are ingested.
liver
How does the musculoskeletal system contribute to homeostasis?
Were it not for the muscles, the body
could not move to the appropriate place at the appropriate time to obtain the foods required for nutrition. The
musculoskeletal system also provides motility for protection against adverse surroundings, without which
the entire body, along with its homeostatic mechanisms,
could be destroyed instantaneously
is
the most abundant of all the end products of metabolism
Carbon dioxide
Passage of the blood through this organ
removes from the plasma most of the other substances
besides carbon dioxide that are not needed by the cells.
kidneys
Substances that the kidneys removes from the plasma
Urea
Uric acid
Excess of ions and water from food
reabsorbed poorly and pass through the renal tubules into
the urine.
Urea
detoxify or remove many drugs and chemicals that are
ingested. Also secretes many of these wastes into the
bile to be eventually eliminated in the feces
liver
three major parts nervous system
sensory input portion,
central
nervous system (or integrative portion), motor output portion
detect the state of the body
or the state of the surroundings.
Sensory receptors
Composed of brain and spinal cord
CNS
Portion of the nervous system that carry
out one’s desires.
motor output portion
important segment of the nervous system . It operates at a subconscious level
and controls many functions of the internal organs, including the level of pumping activity by the heart, movements
of the gastrointestinal tract, and secretion by many of the
body’s glands.
autonomic system
Located in the body are eight
major endocrine glands that secrete chemical substances
called hormones.
Hormone Systems
are transported in the extracellular fluid to all parts of the body to help regulate cellular function.
Hormones
increases
the rates of most chemical reactions in all cells, thus helping to set the tempo of bodily activity.
thyroid hormone
controls
glucose metabolism
Insulin
control
sodium ion, potassium ion, and protein metabolism
adrenocortical hormones
controls bone calcium and phosphate.
Parathyroid hormone
regulates many muscular and secretory activities of the body
Nervous system
regulates
many metabolic functions.
hormonal system
consists of the
white blood cells, tissue cells derived from white blood
cells, the thymus, lymph nodes, and lymph vessels that
protect the body from pathogens such as bacteria, viruses,
parasites, and fungi.
Immune system
Mechanism of WBC
1) distinguish its own cells from
foreign cells and substances
(2) destroy the invader
by phagocytosis or by producing sensitized lymphocytes or
specialized proteins (e.g., antibodies) that either destroy
or neutralize the invader.
is also important
for temperature regulation and excretion of wastes and
it provides a sensory interface between the body and the
external environment.
integumentary system
The skin generally comprises about
how many percent of body weight
12 to 15 percent
The
most intricate control system
that operate in all cells to help control intracellular function and extracellular functions.
genetic control systems
, regulates the concentration of carbon dioxide in
the extracellular fluid.
respiratory system and nervous
system
regulate
the concentration of glucose in the extracellular fluid
The liver and pancreas
Regulated concentrations of hydrogen, sodium, potassium, phosphate, and other ions in the
extracellular fluid.
kidneys
major substances required for
chemical reactions in the cells
Oxygen
control mechanism to maintain an almost exact
and constant oxygen concentration in the extracellular fluid.
It combines with oxygen as a blood passes through the lungs
Hemoglobin
Discuss the oxygen buffering function of hemoglobin
as the blood passes through the tissue capillaries, hemoglobin, because of its own strong chemical affinity for
oxygen, does not release oxygen into the tissue fluid
if too much oxygen is already there. But if the oxygen
concentration in the tissue fluid is too low, sufficient
oxygen is released to re-establish an adequate concentration.
major end product of the oxidative reactions in cells
Carbon dioxide
Fortunately, a higher than normal carbon dioxide concentration in the blood excites the
respiratory center, causing a person to what ?
breathe rapidly and
deeply
In the walls of the bifurcation region of the carotid
arteries in the neck, and also in the arch of the aorta in
the thorax, are many nerve receptors called what? which are stimulated by stretch of the arterial wall.
Baroreceptors
When the arterial pressure rises too high, the baroreceptors send what?
barrages of nerve impulses to the medulla
of the brain
What will happen if potassium ion concentration decreases to less than one-third normal
a
person is likely to be paralyzed as a result of the nerves’
inability to carry signals.
What will happen if the potassium ion
concentration increases to two or more times normal,
the
heart muscle is likely to be severely depressed
When calcium ion concentration falls below about one-half
normal what will happen to a person?
a person is likely to experience tetanic contraction
of muscles throughout the body
When the glucose concentration falls below onehalf normal what will happen to a person?
a person frequently develops extreme mental
irritability and sometimes even convulsions.
a high
concentration of carbon dioxide in the extracellular fluid
increases what?
pulmonary ventilation
, which consists of a series of changes that return
the factor toward a certain mean value, thus maintaining
homeostasis.
negative feedback
better known as a “vicious cycle,”
Positive feedback
Instances where positive feedback can sometimes be useful
Blood clotting
Childbirth
Generation of nerve signals
The brain uses this principle to cause required muscle contraction
Feed forward control
Delayed negative feedback
Adaptive control
