module 2- marine renal

Question 1

T or F: marine mammals have salt-secreting glands

Answer 1

F

Question 2

T or F: marine mammals have long loop of henle so they produce concentrated urine

Answer 2

T

Question 3

how is water retention controlled in marine mammals

Answer 3

hormonal control

Question 4

how to marine mammals obtain freshwater?

Answer 4

metabolizing their blubber produces water

Question 5

what is one of the biggest ways marine mammals lose water?

Answer 5

respiration

Question 6

how does protein breakdown/urea formation work?

Answer 6

protein breakdown produces toxic ammonia (NH3) which is converted to urea (less toxic form) and excreted in urine

Question 7

what is the primary waste product excreted in urine?

Answer 7

urea

Question 8

why is only 50% of urea excreted?

Answer 8

urea passively diffuses into medulla = makes medulla more hypertonic = more water reabsorption via aquaporins = more concentrated urine = less water loss = good

Question 9

urea uses ( ) to suck up more water

Answer 9

aquaporins

Question 10

peritubular capillaries supply the kidney with?

Answer 10

oxygen

Question 11

what is vasa recta

Answer 11

counter flow to loop of henle, picks up what the loop of henle is pumping out

Question 12

vasa recta blood flow

Answer 12

picks up salt & lose water on way down and drops of salt & gain water on the way up

Question 13

why does the vasa recta need to go back up?

Answer 13

blood would be super concentrated and would leave with the salt = lose the gradient = no concentrated urine ever produced