PHGY 216 MODULE 4 EXAM
QUESTIONS AND ANSWERS
homeostatic functions of kidneys (4) - Correct Answers -regulating electrolytes
acid-base control
blood volume
blood pressure
2 compartments of bodies water and percentage - Correct Answers -intracellular fluid:
2/3 of total body fluid
fluid surrounding cells: plasma, interstitial fluid, lymph and trans cellular fluid
plasma is 1/5 of ECF
interstitial fluid is 4/5 of ECF
rest is negligible
three key pools in body - Correct Answers -ICF, plasma and interstitial fluid
all remain distinct
transcellular fluid - Correct Answers -total body water contained in epithelial lined
spaces
barriers between plasma and interstitial fluid and exchange between the two - Correct
Answers -blood vessel walls
at capillary level water and plasma contents can exchange freely with interstitial fluid
composition of plasma and interstitial fluid identical except plasma proteins
change in one causes change in other
barriers between ICF and ECF and exchange between the two - Correct Answers -in
plasma membrane surrounding every cell
ICF contains proteins that don't exchange with ECF
unequal distribution of ions across barrier because no passive movement of ICF or ECF
components across membrane preventing equilibrium being reached
exchange between ICF and external dependent on - Correct Answers -ECF
regulation of ECF and ICF - Correct Answers -ICF tightly regulated by fluid balance
regulated by ECF
two factors regulating fluid balance - Correct Answers -1. ECF volume: related to BP
maintenance, salt balance maintenance important for long-term
2. ECF osmolarity: regulated to prevent shrinking and swelling
, how does ECF change BP - Correct Answers -changes in plasma volume
increasing ECF increases plasma volume and increases arterial BP
short term factors controlling BP until ECF back to normal (2) - Correct Answers -1.
baroreceptor reflex: receptor in carotid and aortic arch detect changes in BP, through
ANS effects on heart and vessels regulate BP
2. fluid shifts: decrease in plasma temporarily compensates shift in fluids out of
interstitial compartment to plasma; opposite occurs also
when are short term factors used for regulation of BP with ECF changes - Correct
Answers -temporary and for minor changes in ECF volumes
total peripheral resistance - Correct Answers -resistance to blood flow due to constricted
blood vessels
high TPR means increased BP
cardiac output - Correct Answers -amount of blood pumped out per minute
long term controls of BP when ECF changes (1) - Correct Answers -fluid input/output:
BP regulation by kidney and thirst mechanism control fluid output and input; control of
urine output critical for long term BP regulation
what makes up 90% of ECF solutes - Correct Answers -sodium and associated anions
salt input regulation - Correct Answers -poor, dependent on dietary salt
necessary to replace lost salt in feces and sweat which is 0.5g/day
average input is 3.5g/day
salt output regulation - Correct Answers -excess salt elimination occurs
in feces, sweat and kidneys (kidneys have biggest role)
osmolarity - Correct Answers -a measure of the concentration of a solute in solution
high osmolarity means more solute and less water in solution
water movement in body purpose and mechanism - Correct Answers -through osmosis
down concentration gradients until osmotic pressure across membrane equalized
reason regulating osmolarity important in preventing cell volume changes
what happens to osmolarity when ECF decreases - Correct Answers -osmolarity
increases so ECF is hypertonic
cells shrink
hypertonic solution - Correct Answers -concentration of solutes within solution greater
than other solution separated by membrane
QUESTIONS AND ANSWERS
homeostatic functions of kidneys (4) - Correct Answers -regulating electrolytes
acid-base control
blood volume
blood pressure
2 compartments of bodies water and percentage - Correct Answers -intracellular fluid:
2/3 of total body fluid
fluid surrounding cells: plasma, interstitial fluid, lymph and trans cellular fluid
plasma is 1/5 of ECF
interstitial fluid is 4/5 of ECF
rest is negligible
three key pools in body - Correct Answers -ICF, plasma and interstitial fluid
all remain distinct
transcellular fluid - Correct Answers -total body water contained in epithelial lined
spaces
barriers between plasma and interstitial fluid and exchange between the two - Correct
Answers -blood vessel walls
at capillary level water and plasma contents can exchange freely with interstitial fluid
composition of plasma and interstitial fluid identical except plasma proteins
change in one causes change in other
barriers between ICF and ECF and exchange between the two - Correct Answers -in
plasma membrane surrounding every cell
ICF contains proteins that don't exchange with ECF
unequal distribution of ions across barrier because no passive movement of ICF or ECF
components across membrane preventing equilibrium being reached
exchange between ICF and external dependent on - Correct Answers -ECF
regulation of ECF and ICF - Correct Answers -ICF tightly regulated by fluid balance
regulated by ECF
two factors regulating fluid balance - Correct Answers -1. ECF volume: related to BP
maintenance, salt balance maintenance important for long-term
2. ECF osmolarity: regulated to prevent shrinking and swelling
, how does ECF change BP - Correct Answers -changes in plasma volume
increasing ECF increases plasma volume and increases arterial BP
short term factors controlling BP until ECF back to normal (2) - Correct Answers -1.
baroreceptor reflex: receptor in carotid and aortic arch detect changes in BP, through
ANS effects on heart and vessels regulate BP
2. fluid shifts: decrease in plasma temporarily compensates shift in fluids out of
interstitial compartment to plasma; opposite occurs also
when are short term factors used for regulation of BP with ECF changes - Correct
Answers -temporary and for minor changes in ECF volumes
total peripheral resistance - Correct Answers -resistance to blood flow due to constricted
blood vessels
high TPR means increased BP
cardiac output - Correct Answers -amount of blood pumped out per minute
long term controls of BP when ECF changes (1) - Correct Answers -fluid input/output:
BP regulation by kidney and thirst mechanism control fluid output and input; control of
urine output critical for long term BP regulation
what makes up 90% of ECF solutes - Correct Answers -sodium and associated anions
salt input regulation - Correct Answers -poor, dependent on dietary salt
necessary to replace lost salt in feces and sweat which is 0.5g/day
average input is 3.5g/day
salt output regulation - Correct Answers -excess salt elimination occurs
in feces, sweat and kidneys (kidneys have biggest role)
osmolarity - Correct Answers -a measure of the concentration of a solute in solution
high osmolarity means more solute and less water in solution
water movement in body purpose and mechanism - Correct Answers -through osmosis
down concentration gradients until osmotic pressure across membrane equalized
reason regulating osmolarity important in preventing cell volume changes
what happens to osmolarity when ECF decreases - Correct Answers -osmolarity
increases so ECF is hypertonic
cells shrink
hypertonic solution - Correct Answers -concentration of solutes within solution greater
than other solution separated by membrane
