50 terms

chapter 24 BALANCE

most of the body water is in
the intracelluar fluid (ICF)
osmosis from one fluid compartment to another is determined by
the relative concentration of solutes in each compartment
in which of these compartments would fluid accumulate in edema
tissue (interstitial) fluid
most body water comes from ____ whereas most body water is lost via ____
drinking; urine
fluid intake is governed mainly by hypothalamic neurons called
antidiuretic hormone (ADH)
promotes water conservation
water output is significantly controlled through variations in
urine volume
when blood volume and pressure are too high
ADH release is inhibited
prolonged exposure to cold weather can lead to
a negative water balance
dehydration results in increased blood and ECF osmolarity. this makes osmoreceptors stimulate ____ secretion by the hypothalamus ___ in the DCT and CD
ADH; increasing water reabsorption
decrease body water but do not significantly affect osmolarity
long-term inhibition of thirst is mostly associated with
a drop in blood osmolarity
this is the principal cation of the ECF
aldosterone receptors are found on cells of
the distal convoluted tubule (DCT)
increases Na+ reabsorption and K+ secretion
hypernatremia is a plasma ____ concentration above normal
hypernatremia tends to cause all of the following except
a reduction in plasma volume
____ is the most significant solute in determining the distribution of water among fluid compartments
____ does not stimulate aldosterone secretion
high blood sodium concentration
women have a tendency to retain water during part of the menstral cycle because estrogen mimics the action of
this is the most abundant cation of the ICF
the total body water (TBW) content of a 70 kg young male is about
40 L
this is the greatest determinant of intracellular volume
these scenarios are related with hyperkalemia except
resting membrane potential is more negative
in a state of hypokalemia
cells are hyperpolarized
hypokalemia can result from all of the following except from
aldosterone hyposecretion
this is the most abundant anion of the ECF
chloride homeostasis is achieved mainly as a result of ____ homeostasis
the calcium of the body fluids does/is not
a significant component of nucleic acids
calcium concentration is regulated by
the inorganic phosphates (Pi) of the body fluids do/are not
form crystals with calcium in the presence of calsequestrin
excretion of phosphate
increases free calcium ions in the ECF
____ represents the complete chemical equation for the bicarbonate buffer system
CO2 + H2O --> H2CO3 --> HCO3- + H+
tissue fluid normally has a pH of
the major chemical buffers system of the body are the ___ systems
bicarbonate, phosphate, and protein
what protein(s) is/are the most important buffer(s) in blood plasma
what protein(s) is/are the most important buffer(s) in erythrocytes
a weak base
binds little H+ and has weak effect on pH
when the renal tubules secrete hydrogen ions into the tubular fluid, they ___ at the same time
reabsorb sodium
the pH of the intracellular fluid is buffered mainly by
the bicarbonate buffer system would not work very well in the human body is not for the action of the respiratory system, which
expels CO2 produced by the buffer system
an antiport system on the basal side of the renal tubule cells
exchanges K+ for Na+
proteins can buffer a drop of pH by their ____ side groups and can buffer an increase in pH by their ____ side groups
in a person with normal acid-base balance, there are no bicarbonate ions in urine because
they are consumed by neutralizing H+
in acidosis, the membrane potential of nerve cells is ___, which ____ the central nervous system
hyperpolarized; depresses
in acidosis, the kidneys compensate by
secreting more ammonia
breathing with the head inside a plastic bad can lead to
respiratory acidosis
excessive intake of antacids can lead to
metabolic alkalosis
chronic vomiting can lead to
metabolic alkalosis
emphysema can lead to
respiratory acidosis