CHAPTER 17

Question 1

explain co-current exchange in fish

Answer 1

if fish swim backwards the blood and water would flow in the same direction.

Question 2

Why can the PH of the plasma be different from the PH of the cerebrospinal fluid?

Answer 2

The red blood cells in the plasma contain proteins that use H+ as a buffer. In the CF H+ concentrations depend on the amount of CO2 because of the equation. an increase of H+ will decrease the PH of the CF

Question 3

CO2+H2O–> H2CO3 –>

Answer 3

H+ + HCO3-

Question 4

If you were to exercise a lot what chemoreceptor are you using?

Answer 4

The peripary chemoreceptors

Question 5

following a 15 sec breathing of fresh air the O2 content of plasma? HYPERVENTILATION

Answer 5

stays the same because the hemoglobin amounts are still saturated

Question 6

following a 15 sec breathing of fresh air the CO2 content of plasma? HYPERVENTILATION

Answer 6

decreases reduced PP of CO2 in plasma–> drastically

HYPERV GETS RID OF CO2

Question 7

avelour PP=

Answer 7

systemic atreal PP

Question 8

How is NA+ concentration regulated in the aplical membrane of the cells

Answer 8

The regualtion site are the sodium and potassium channals.

Question 9

what happens if the amount of NA+ channals increseas

what happens if the amount decreases

Answer 9

increases= increased reaborbtion of Na+ which will incresse the amount of na+ that is being activily pumped out of the cell into the plasma 
decrease= na+ will not enter the cell

Question 10

what determines the cells permabilty to water

Answer 10

the amount of aqua-pouarns in the cell

Question 11

true or false?

H2O permablity is low in the loop of helen

Answer 11

false

permablilty is high

Question 12

what is the permablilty of H2O at the ascending loop of henle

Answer 12

zero

Question 13

why is the mOSM 1200 and the bottom of the loop of henle

Answer 13

there is a driving force for water to leave but no NA+ leaves

Question 14

what happens where there is an absence of VASOPRESSIN

Answer 14

the permeability of the cell to water decreases because there are fewer aqua channels in the apical membrane of the cell.

Question 15

how do you produce dilute urine

Answer 15

a decrease in the number of aqua-pores in the principle cells will produce more dilute urine with a low mOSMO.

Question 16

true/false

Urine at 1200mOSMO and 100mOsmo have the same solute concentration

Answer 16

true.

Question 17

what occurs when an individaul losses the ability to produce vasopresiant

Answer 17

they have diabetes insipidus and have less aquapors in the collecting duct which will result in less water being reabsorbed and more urine.

Question 18

what is the difference between an osmotic diuresis and an H2O diuresis

Answer 18

Osmotic diuresis- is due to the inability to absorb solute(glucose) –> cannot establish a large osmotic gradient

H2O diuresis- loss of the ability to produce vasopressin–. less water reabsorption more urine production.

Question 19

how does alcohol effect urine production?

Answer 19

alcohol blocks the release of vasopressin which decreases the number of aquaporins in the principle cells which decreases the amount of water absorbed –> leads to an increase of urine