Tubular processing of the glomerular filtrate. Proximal tubular reabsorption

Question 1

filtration - location

Answer 1

glomerulus = capillary network surrounded by bowman capsule

Question 2

filtration - process

Answer 2

1 - blood filtered through glomerular capillaries
2 - filtrate passes into bowmans capsule
- proteins/ bloods cannot filter through so stay inside bloodstream

Question 3

filtration - result

Answer 3

filtrate is similar to plasma
filtrate does not contain proteins/ bloods

Question 4

reabsorption - location

Answer 4

PCT
loop of henle
DCT
collecting duct

Question 5

proximal convoluted tubule - 1

Answer 5

sodium
- active transport from tubular cells into blood
- na/k-ATPase pump on basolateral membrane

Question 6

proximal convoluted tubule - 2

Answer 6

water
- passively by osmosis due to high osmolarity in interstitial space
- aquaporins channels

Question 7

proximal convoluted tubule - 3

Answer 7

nutrients = glucose/ amino acids
- active transport

Question 8

proximal convoluted tubule - 4

Answer 8

electrolytes = cl-/ hco3-

• passively reabsorbed
• to help acid-base balance in body

Question 9

proximal convoluted tubule -5

Answer 9

secretion
to excrete/ remove waste like drugs

Question 10

descending limb - 1

Answer 10

• highly permeable to water
• impermeable to solutes na+/k+/cl-

Question 11

descending limb - 2

Answer 11

when filtrate moves through descending limb, water gets reabsorbed into surrounding hypertonic interstitial fluid of medulla

filtrate gets more concentrated as it moves through medulla

Question 12

ascending limb - 1

Answer 12

thick ascending limb

• impermeable to water so filtrate gets diluted as moves through the loop of henle

Question 13

ascending limb - 2

Answer 13

thick ascending limb

• moves solutes by secondary active transport
• by sodium-potassium-chloride cotransporter from filtrate into TAL
• na/k ATPase pump takes sodium into interstitium forming a concentration gradient for sodium reabsorption

Question 14

ascending limb - 3

Answer 14

filtrate gets diluted as nacl gets removed without water coming out

Question 15

distal convoluted tubule - 1

Answer 15

sodium

• sodium reabsorbed by na+/cl- symporter + na/k ATPase pump
• enhanced by aldosterone

Question 16

distal convoluted tubule - 2

Answer 16

potassium

secreted into filtrate in exchange for sodium

Question 17

distal convoluted tubule - 3

Answer 17

calcium

• calcium reabsorbed in exchange for sodium by sodium/ calcium exchanger _ calcium channels
• under regulation of PTH

Question 18

distal convoluted tubule - 4

Answer 18

water

• impermeable to water
• ADH can help water to be reabsorbed

Question 19

distal convoluted tubule - 4

Answer 19

DCT controls pH balance by secreting H+ into filtrate / reabsorbs HCO3-

Question 20

distal convoluted tubule - 5

Answer 20

DCT controls pH balance by secreting H+ into filtrate / reabsorbs HCO3-

Question 21

collecting duct - 1

Answer 21

sodium

• reabsorbed into collecting duct needed into body for blood volume/ pressure
• enhanced by aldosterone as it activated sodium channels

Question 22

collecting duct - 2

Answer 22

potassium

• secreted into collecting duct needed for cell function
• enhanced by aldosterone

Question 23

collecting duct - 3

Answer 23

water

• collecting duct is highly permeable to water
• enhanced by ADH

Question 24

secretion - 1

Answer 24

• h+ for acid base balance

Question 25

secretion - 2

Answer 25

creatinine/ urate/ drugs for excretion