Renal: Urine Concentration and Dilution Mechanisms Flashcards Preview

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Flashcards in Renal: Urine Concentration and Dilution Mechanisms Deck (27):
1

Osmoreceptors that sense osmolarity

Osmoreceptors

2

ADH is released from which Pituitary Gland?

Posterior Pituitary

3

True/False:

Changes in Blood Osmolarity changes ADH release

True

4

What Hormone concentrates Urine?

ADH

5

Which part of the Loop of Henle is the concentrating segment?

Descending limb of Loop of Henle

6

Which part of the Loop of Henle is the diluting segment?

Thick Ascending limb of Loop of Henle
Thin Ascending limb of Loop of Henle

7

What is the difference between Nephrons?

Placement and Length of Loop of Henle

8

Concentrations _____ while moving down Loop of Henle

Increase. Up to about 1200mOsm/L

9

pumps against 200mOsm gradient. 200mOsm maximum difference between outside and inside (higher on the outside)

Sodium-Potassium-2 Chloride Transporter (mostly on Ascending but some on Descending)

10

Countercurrent Mutltiplier System

Loop of Henle

11

Countercurrent Exchanger System

Vasa Recta

12

Isoosmotic level

300mOsm/L

13

Urea contributes to hyperosmotic medulla. Urea contributes how much of the osmolarity of renal medullary interstitium?

40%

14

Which parts of the Nephron are relatively impermeable to Urea?

Ascending Limb of Loop of Henle, Distal tubule, and Cortical Collecting Duct are relatively impermeable to urea

15

Which part of the Collecting Duct is very permeable to Urea?

Inner-medullary Collecting Ducts very permeable to urea (even more so with ADH)

16

Which parts of the Nephron have some reabsorption to Urea?

Proximal Tubule

17

Which part of the Nephron Urea diffuses into?

Descending Limb of Loop of Henle

18

Urea recycling

Urea moves in and out of Nephron

19

Vasa Recta surrounds which type of Nephron?

Juxtamedullary Nephrons

20

Peritubular Capillaries surrounds which type of Nephron?

Cortical Nephrons

21

Difference between Vasa Recta and Loop of Henle?

Loop of Henle makes the concentration gradient

Vasa Recta aids the Loop of Henle function, preserves concentration gradient

22

What helps to preserve hyperosmolarity of the renal medulla?

Vasa Recta

23

What are the 2 characteristics of the Vasa Recta?

1. Medullar blood flow is low
2. Vasa Recta serve as countercurrent exchangers

24

How does the Vasa Recta preserve the gradient?

As solutes move into blood, solutes move back into the interstitium instead of "washing out" gradient

25

What 4 factors impact Urine Concentration?

1. Plasma level of ADH
2. Osmolar concentration of interstitial fluid surrounding the collecting ducts
3. Urea recycling
4. Vasa recta

26

Dehydration leads to a more ______ Urine

Concentrated (higher osmolarity)

27

Hydration leads to a more _______ Urine

Diluted (lower osmolarity)