65 terms

ch. 24

Blood plasma osmolarity is higher than intracellular fluid osmolarity
in a state of water balance, average daily fluid gains and losses are equal
fluid intake is governed mainly by hypothalamic receptors called osmorecepters
the kidneys secrete ADH in response to dehydration
hypovolemia refers to a deduction in total body water while maintaining normal osmolarity
aldosterone promotes potassium excretion
natriuretic peptides promote sodium and potassium excretion
hyponatremia is usually a result of hypotonic hydration
hypocalcemia causes muscle weakness, whereas hypercalcemia causes potentially fatal muscle tetanus
chloride homeostasis is regulated as a side effect of sodium homeostasis.
a buffer system converts a weak acid or base into a strong one.
the three physiolovical buffer systems are urinary, digestive, and respiratory.
the kidneys neutralize more acid or base than any other buffer system.
acidosis is a ph lower than 7, whereas alkalosis is a ph higher than 7
uncompensated alkalosis is a ph imbalance that can only be corrected with clinical intervention.
most of the body water is in
the intracellular 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
promotes water conservation
water output is significantly controlled through variation 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 osmoreceptores 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 foudn oc cells of
the distal convoluted tubule (DCT)
Increases Na+ reabsorption and K+ secreation
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 menstrual cycle because estrogen mimics the action of
this is the most abundant cation of the ICF
the total body water (TBW) contente of a 70 kg young male is about
40 L.
this is the greatest determinant of intracellular volume
these scenarious are related with hyperkalemia except
resting membrane potential is more negative
is a state of hypokalemia
cells are hyperpolarized
hypokalemia can result from all of the following except from
aldosterone hyposecretion
this is the moste abundant anion of the ECF
chloride homeostasis is achieved mainly as a result of_____ homeostasis
the calcium of the body fluids
is not a significant component of nucleic acids
calcium concentration is regulated by
the inorganic phosphates (Pi) of the body fluids
form crystals with calcium in the presence of calsequestrin
excretion of phosphate
increases free calcium ions in the ECF
___ represents the complete chemical reaction for the bicarbonate buffer system.
CO2 + H2O <--> H2CO3 <--> HCO3- + H+
tissue fluid normally has a pHof
The major chemical buffers systems 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 a weak effect of 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 if not for the action of the respiratory sytem, which
expels CO2 produced by the buffer system
an antiport system on the basal side of renal tubule cells
exchanges K+ for Na+
Proteins can buffer a drop in 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 bag can lead to
respitory acidosis
excessive intake of antacids can lead to
metabolic alkalosis
chronic vomiting can lead to
metabolic alkalosis
emphysema can lead to
repiratory acidosis