Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

HUBS192 2024 > Lecture 31 > Flashcards

Lecture 31 Flashcards

1
Q

What is filtration?

A

Movement of plasma from the glomerular capillaries into the glomerular capsule

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

What does filtration create?

A

Plasma-like filtrate

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

What determines glomerular filtration?

A

Filtration barrier, renal blood flow and driving forces

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

What is filtered?

A

Small substances with low molecular masses

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

What isn’t filtered?

A

Large substances with high molecular masses

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

What happens to the substances that aren’t filtered?

A

They remain in the capillaries, exiting the glomerular capillaries via the efferent arteriole and then traveling to the peritubular capillaries

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

What is renal blood flow?

A

The amount of blood that flows through the kidneys per unit time

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

How much cardiac output do the kidneys reciece?

A

20% at rest

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

What is the numerical value for healthy renal blood flow?

A

1100-1200 mL of blood / minute

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

What is the high blood flow through the kidneys for?

A

Filtration (not metabolism)

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

What are the two glomerular driving forces

A

Hydrostatic pressures and colloid osmotic pressures

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

What is the hydrostatic pressure due to?

A

The volume of fluid present

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

What does the hydrostatic pressure driving force cause in the glomerulus?

A

A push of fluid away from the glomerular capillaries

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

What is the colloid osmotic pressure due to?

A

Proteins - like a magnet

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

What does the colloid osmotic pressure driving force cause in the glomerulus?

A

A pull of fluid into the glomerular capillaries

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

What is a positive pressure?

A

A pressure favouring filtration

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

What is a negative pressure?

A

A pressure opposing filtration

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

What are the two hydrostatic forces in the glomerulus?

A

Glomerular hydrostatic pressure and capsular hydrostatic pressure

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

What is the glomerular hydrostatic pressure due to?

A

Blood pressure

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

What is the value for glomerular hydrostatic pressure?

A

+ 50 mmHg

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

What is the capsular hydrostatic pressure due to?

A

Pressure of filtrate already present

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

What is the value for capsular hydrostatic pressure?

A

-15 mmHg

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

What are the two colloid osmotic pressures?

A

Blood colloid osmotic pressure and capsular colloid osmotic pressure

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

What is the blood colloid osmotic pressure due to?

A

Albumin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the value for blood colloid osmotic pressure?

A

-25 mmHg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the capsular colloid osmotic pressure due to?

A

There is none because there are no proteins in the capsular space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the value for capsular colloid osmotic pressure?

A

0 mmHg

28
Q

What is the value of net filtration pressure?

A

+ 10 mmHg

29
Q

What is filtration fraction?

A

The proportion/percentage of the kidneys plasma flow that is filtered

30
Q

What is the value for filtration fraction?

A

20% of plasma entering the kidneys

31
Q

What is the glomerular filtration rate (GFR)?

A

The amount of plasma filtered per unit time

32
Q

What is the value for healthy glomerular filtration rate?

A

125mL / min

33
Q

How do you find glomerular filtration rate?

A

Renal plasma flow x filtration fraction

34
Q

How much plasma is filtered per day?

A

Normally 180 L

35
Q

How much urine is produced per day

A

~1.5L

36
Q

What percentage of plasma-like filtrate is reabsorbed?

A

> 99%

37
Q

What happens to glomerular filtrate rate as you age?

A

It slowly declines

38
Q

What is renal filtered load?

A

How much of a substance in the plasma is filtered per unit of time

39
Q

What is the filtered load equation?

A

glomerular filtration rate x solute plasma concentration

40
Q

What is renal clearance?

A

How much plasma is cleared of a substance per unit time

41
Q

What are the filtration characteristics of creatinine?

A

Freely filtered, not secreted or reabsorbed so all that is filtered is excreted in urine

42
Q

What is the renal clearance of creatinine?

A

Glomerular filtration rate

43
Q

What are the filtration characteristics of PAH (medications and toxins)?

A

Freely filtered, entirely secreted and none reabsorbed so all that flows through kidneys is excreted in urine

44
Q

What is the renal clearance of PAH (medications and toxins)?

A

Volume of plasma flowing through the kidneys per minute (RPF)

45
Q

What are the filtration characteristics of glucose?

A

Freely filtered, not secreted but all is reabsorbed so none is in urine

46
Q

What is the renal clearance of glucose?

A

0

47
Q

What are the filtration characteristics of Sodium?

A

Freely filtered, not secreted and nearly entirely reabsorbed so very little is excreted in urine

48
Q

What is the renal clearance of sodium?

A

A very small volume of plasma per minute

49
Q

What is Ux?

A

Concentration of x in urine (mmol/L)

50
Q

What is V?

A

Volume of urine produced per unit time (mL/min)

51
Q

What is Px?

A

Concentration of x in plasma (mmol/L)

52
Q

How can we estimate glomerular filtration rate?

A

Using renal clearance

53
Q

What are the requirements of a substance to be able to measure GFR?

A

To be freely filtered, not reabsorbed nor secreted

54
Q

What are the two main substances that meet the requirements to measure GFR?

A

Inulin and creatinine

55
Q

What is inulin?

A

A polysaccharide that is not metabolised or found in the body. It must be injected

56
Q

What is creatinine?

A

A waste product produced by muscles therefore it is already in the body and most commonly used clinically

57
Q

What is your GFR if you have two healthy, working kidneys?

A

125 mL/min

58
Q

What is your GFR if you have one healthy, working kidney?

A

60 mL/min

59
Q

What happens when your GFR is < 25 mL/min

A

Plasma creatinine concentration increases as the kidneys ability to clear waste product is reduced

60
Q

What happens when your GFR is <15 mL/min?

A

Kidney failure, the kidney’s ability to clear waste products from the blood is greatly reduced

61
Q

What is the value for renal plasma flow (RPF)?

A

625 mL/min

62
Q

What is the renal clearance of sodium?

A

<1 mL/min

63
Q

What is the renal clearance of glucose?

A

0 mL/min

64
Q

What is the renal clearance of medications and toxins?

A

625 mL/min

65
Q

What is the renal clearance of creatinine and inulin?

A

125 mL/min

HUBS192 2024 (38 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions