Countercurrent multiplication Flashcards
1
Q
What does the proximal convoluted tubule do?
A
- Reabsorbs ions-> sodium, chloride, amino acids, glucose and water
- Reabsorbs 65% of all important nutrients
2
Q
Function of Loop of Henle?
A
- Renal medulla: salty due to ion reabsorption
- Descending limb- reabsorbs water- impermeable to ions- no ions are reabsorbed at this point
- Ascending limb- reabsorbs sodium, chloride, potassium- impermeable to water- no water absorbed at this point
3
Q
Countercurrent multiplication
A
- Descending limb and ascending limb go in opposite direction- countercurrent
- Multiplication- when ions are reabsorbed in the ascending limb and make the medulla salty by not reabsorbing water causes water to be reabsorbed passively in the descending limb.
4
Q
How is water reabsorbed in the loop of Henle?
A
- Water is absorbed passively
- No energy is used to reabsorb water
5
Q
How are ions reabsorbed in the loop of Henle?
A
- Use energy to reabsorb ions (active transport)
6
Q
How does counter current multiplication work?
A
- By actively pumping ions into the medulla and no water in the ascending limb (to make salty) they multiply the amount of water reabsorbed passively (by osmosis)
7
Q
Distal convoluted tubule function?
A
- Responsible for the reabsorption of other ions (sodium, chloride)
- Picks up important nutrients
8
Q
Juxtaglomerular appartus
A
- Controls blood pressure (comes in contact with glomerulus)
9
Q
Why do kidneys keep some urea?
A
- To increase osmolarity in the medulla
- Urea recycling- reabsorbed to maintain osmolarity
10
Q
How does capillaries assist reabsorption?
A
- Capillaries go across nephron and reabsorbs nutrients and ions from interstitium (peritubular capillaries)-> goes into renal vein and takes it to body
11
Q
What is the interstitum?
A
- Anything not a tubule or vessels
