Ch 25 Urinary Part 2 Flashcards

1
Q

What are the 2 classes of nephrons?

A

Cortical and Juxtamedullary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where are the cortical nephrons located?

A

entirely in cortex and are more numerous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are juxtamedullary nephrons important? What do they do?

A

important in the production of the urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What consists of the juxtamedullary nephrons?

A
  • long nephron loops deeply invaded in the medulla

- thick and thin acesending limbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do the mansa dansa cells do?

A

they act as chemoreceptors that monitor NaCl concentration of filtrate entering DCT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What do the Granular cells do?

A

smooth muscles cells that secrete renin. They act as mechanoreceptors that sense blood pressure in the afferent arteriole.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does the extraglomerular do? (mesengial)

A

passes signals between mansa densa cells and granular cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the afferent arteriole supply?

A

The glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What drains the glomerulus?

A

the efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does the glomerular filtration do?

A

produces cells and protein free filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does tubular reabsorption do?

A

moves substances from filtrate back to blood (glucose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does tubular secretion do?

A

moves substances from blood that couldn’t pass through the filtration membrane into the filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Urine is produced from _____

A

Filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Filtrate is produced via ____

A

glomerular filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The percent of blood plasma entering glomeruli that becomes glomerular filtrate

A

filtration fraction (16-20 % is normal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

In the filtration membrane blood comes in the

A

larger afferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens when the filtration membrane is constricted?

A

its shunts and cuts of blood meaning less fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does the glomerular capsule space do in the membrane filtration?

A

caputures filtrate that escapes from glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the 3 layers of the filtration membrane

A

capillary endothelium
basement membrane
foot processes of podocyte of glomerular capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does the capillary endothelium do?

A

contains fenestrations that blocks blood cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What doe the basement membrane do?

A

it blocks all the smallest proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What do the foot processes of podocytes do?

A

they are little spaces with with filtration slits and slit diaphragm that block macromolecules (large proteins, polysaccharides)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is filtration (in membrane) ?

A

flow of liquid through a membrane due to hydrostatic pressure (pressure inside capillaries that pushes through filtration membrane)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Who holds greater volume of fluid? Capillaries of filtration membrane of glomeruli?

A

filtration membrane of glomeruli

25
Q

What molecules does the filtration membrane allow to pass?

A

has to be smaller than 3nm

water, glucose, amino acids, nitrogenous wastes

26
Q

Why are plasma proteins remained in the blood?

A

to maintain colloid osmotic pressure
prevents water loss of capsular space
proteins in filtrate indicate membrane problem

27
Q

Hydrostatic pressure in glomerular capillaries

A

glomerular blood pressure

55 mm HG

28
Q

What does the hydrostatic pressure in the glomerular capillaries do?

A

forces fluid out of glomerulus into glomerular capsule space

29
Q

Hydrostatic pressure in capsular space

A

filtrate pressure in capsule

15 mm Hg

30
Q

What does the hydrostatic pressure do in capsular space?

A

pushes back into glomerulus

31
Q

colloid osmotic pressure in capillaries

A

pull of proteins in blood 30 mmHg

32
Q

What is the net filtration pressure?

A

sum of forces

33
Q

If pressure was higher than normal, would the NFP go up or down?

A

Up to produce more urine

34
Q

What is the glomerular filtration rate?

A

vol of filtrate formed per min by kidneys

35
Q

What is the GFR ( glomerular filtration rate) proportional to?

A

Net filtration pressure
total surface area available for filtration
filtration membrane permeability

36
Q

What does tubular reapsorption do?

A

quickly reclaims most of the tubular contents (filtrate) and returns them to blood

37
Q

Where does tubular reasporbtion occur?

A

In renal tubules

38
Q

What is Tubular secretion?

A

reabsorption in reverse

forces things from blood INTO filtrate

39
Q

What does tubular secretion occur?

A

in the PCT to contron blood ph

40
Q

What is the transcellular route for tubular reabsorption?

A
  1. transport across the apical membrane
  2. diffusion across the cytosol
  3. Transport across the basolateral membrane
  4. movement through the interstitial fluid and into capillary
41
Q

Paracellular route for tubular reabsorption

A
  1. movement through leaky tight junctions particularly in PCT
  2. movement through the interstitial fluid into capillary
42
Q

What happens during the tubular reabsorption of Na?

A

allows water and other solutes to be reabsorbed

43
Q

What is sodium potassium pump? (Location, Function)

A

located in the basolateral membrane
pumps Na into intersitial space
uses 6% daily ATP (active transport process)

44
Q

Na K pump establishes concentration gradient for..

A

secondary active transport

45
Q

Organic nutrients that reabsorbed by secondary active transport and are cotransported with Na +

A

glucose, amino acids, some ions and vitamins

46
Q

Tubular reabosrption of water/nutrients via active/passive transport steps

A
  1. at Basolateral membrane Na+ is pumped via Na K pump. Active transport creates concentration gradients that drive…
  2. Downhill Na+ entry at the apical membrane
  3. Reabsporion
47
Q

Tubular reabosrption of water/nutrients via active/passive transport steps

A
  1. at Basolateral membrane Na+ is pumped via Na K pump. Active transport creates concentration gradients that drive…
  2. Downhill Na+ entry at the apical membrane
  3. Reabsporion of organic nutrients and ions by contransport at apical membrane
  4. Reabsorption of water by omosis via aquaporins. water reabosorption increases the concentration of solutes that are left behind. these solutes can then be reabsorped as the move down gradients
    1. lipid soluble substances diffused by transcellular route
    2. Various ions (Cl Ca K) and urea diffuse by paracellular route
48
Q

When carriers for a solute is saturated, excess is exerted into ___.

A

urine

49
Q

Transport maximum

A

exists for every reabosrbed susbtance and reflects the number of carriers in renal tubules that are available

50
Q

What is hyperglycemia and what does it lead to regarding transport maximum

A

leads to high blood glucose levels that exceed Tm , and glucose spills over into urine

51
Q

Filtrate volume that is reabosorbed in PCT

A

65 % of filtrate vol is reabsorbed
H20, Na+ and HCO3-
Glucose, amino acids, and other nurtrients

52
Q

What does the PCT secrete?

A

H+ and NH4+ and some drugs

53
Q

The descending limb absorbs…

A

water

54
Q

What does the DCT absorb?

A

Na+ (aldestrone) and Ca+ (parathyroid)

55
Q

What does the DCT secrete?

A

K+ by aldostrone

56
Q

What does the ascending limb absorb?

A

Na+ K+ Cl-

57
Q

What does the ascending limb secrete?

A

urea

58
Q

What does the collecting duct absorb?

A

H20 (by ADH)
Na+ (by Aldosterone) Cl- follows
Urea (increased by ADH)

59
Q

What does the collecting duct secrete?

A

K+ by aldosterone