Lecture 24

Question 1

What is the extracellular fluid?

Answer 1

protein-free plasma

Question 2

What is the fluid entering the proximal tubule?

Answer 2

dilute urine

Question 3

How much fluid is filtered at the renal corpuscle per day?

Answer 3

180 L

Question 4

What are podocytes?

Answer 4

epithelium around the glomerular capillaries

Question 5

What are in between eh foot processes of the podocytes? What is its function?

Answer 5

filtration slits = allows filtrate to pass through

Question 6

What is the mechanism of filtrate movement from afferent arterioles into the lumen of the nephron?

Answer 6

passive | due to high pressure in the afferent arteriole

Question 7

What does protein in the urine indicate?

Answer 7

issue with the kidney

Question 8

What is the ENaC?

Answer 8

epithelial sodium channel/carrier | takes up sodium from lumen and into ECM

Question 9

What is the SGLT?

Answer 9

sodium glucose transporter | glucose and sodium from lumen into ECM

Question 10

What is GLUT?

Answer 10

passive glucose transporter | glucose into ECM

Question 11

What is the NaDC?

Answer 11

sodium dicarboxylate cotransport

Question 12

Where does the body want the organic anions and the aKG?

Answer 12

trade the organic anions for the aKG = excrete organic anions

Question 13

What is the endpoint of the organic anions and aKG transport across the nephron lumen?

Answer 13

excrete organic anions into lumen

Question 14

Which side has a high concentration of aKG and organic anions to begin with?

Answer 14

tubule lumen = high aKG | ECM = high organic anions

Question 15

What is reabsorbed by the time fluid reaches the end of the nephron?

Answer 15

glucose, amino acids, water, ions, and useful emtabolites

Question 16

What is renal clearance?

Answer 16

rate at which the solute disappears from the body by excretion or metabolism

Question 17

What molecule has a 100% renal clearance?

Answer 17

inulin

Question 18

What molecule has a 0% renal clearance?

Answer 18

glucose

Question 19

What does the presence of glucose in urine indicate?

Answer 19

an issue

Question 20

What is microurition?

Answer 20

urinate

Question 21

What happens to smooth muscle when the bladder is empty?

Answer 21

smooth muscle not stretched = bladder continues to be filled

Question 22

What happens to the smooth muscles when the bladder is getting full?

Answer 22

stretch receptors on smooth muscle bladder cells = send signal to CNS = contract bladder muscle = relax sphincter = pee

Question 23

What part of the CNS controls urination?

Answer 23

spinal cord

Question 24

What is reabsorbed in the descending limb? What kind of transport mechanism is used?

Answer 24

only water | passive transport

Question 25

What is reabsorbed in the ascending limb? What kind of transport mechanism is used?

Answer 25

only solutes | active transport

Question 26

What is the counter-current mechanism (multiplication)?

Answer 26

movement of filtrate in two opposite directions

Question 27

What does the counter-current mechanism establish?

Answer 27

different concentration gradients within the medulla

Question 28

What does the counter-current mechanism dictate?

Answer 28

how concentrated the urine will be when it is excreted out of the kidney

Question 29

What happens if there is improper excretion of waste from the body? What can it cause?

Answer 29

build-up of uric acid = causes gout

Question 30

What is an anti-diuretic?

Answer 30

body not allowed to excrete water

Question 31

What is the effect of anti-diuretic hormones on the collecting duct epithelium?

Answer 31

more permeable to water

Question 32

What happens when vasopressin binds to the receptor on the epithelial cells of the collecting duct?

Answer 32

second messenger system = insert more water channels on the apical membrane of epithelial cell

Question 33

Which aquaporin (1 or 2) is dependent on vasopressin?

Answer 33

aquaporin-2

Question 34

Which aquaporin is not controlled by vasopressin (1 or 2)?

Answer 34

aquaporin-1

Question 35

What are the 3 stimuli that control the secretion of vasopressin?

Answer 35

plasma osmolarity | blood volume | BP

Question 36

What is the function of osmoreceptors?

Answer 36

detects changes in water levels in the blood (not enough water = increase osmolarity = trigger vasopressin secretion)