Brainscape's Knowledge GenomeTM

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


See full index

Kidney > Filtration > Flashcards

Filtration Flashcards

1
Q

Define glomerular filtration rate? (GFR)

A

Passage of fluid from the blood into Bowman’s space

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

State 6 factors that determine glomerular filtration rate?

A

1) Pressure gradients
2) Size of the molecule
3) Charge of the molecule
4) Rate of blood flow
5) Surface area; directly proportional to membrane permeability and surface area
6) Binding to plasma proteins e.g. Ca2+, hormones, fatty acids

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

What is GFR value?

A

125ml/min

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

What does 125ml/min represent?

A

GFR

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

What percentage of plasma passes through glomerulus?

A

20%

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

State GFR formula?

A

GFR = (UrineM x urine flow rate) / PlasmaM
M= conc x volume

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

How to calculate M in fluid? (creatine)

A

Concentration x Volume

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

Why is measuring GFR used in clinical settings?

A

Disease cause loss nephrons
GFR fall

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

What is used calculate GFR?
Why?

A

Creatine
Freely filtered by glomerulus but not secreted or absorbed in tubules and not metabolised

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

What is function of creatine in diagnostic tests?
Why?

A

Used estimate GFR
Freely filtered by glomerulus
Not secreted/absorbed in tubules
Not metabolised

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

Define myogenic autoregulation?

A

Smooth muscle contraction in response to external stretching force, occurs in capillary walls, passive mechanism

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

If increased NaCl conc what will occur to afferent arteriole?

A

Constrict

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

If decreased conc NaCl what will occur afferent arteriole?

A

Dilation

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

What causes fast response in arterioles?

A

GFR

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

What causes slow response in arterioles?

A

RAAS

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

State value normal GFR?
in 24 hrs?

A

125ml/min
180L in 24 hrs

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

How much of GFR is reabsorbed?

A

99%

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

What is total plasma volume?
IF? Transcellular?

A

3L
IF- 2 Transcellular- 1

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

How many times in 24hrs is plasma volume filtered?

A

60 times/day

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

What is value hydorstatic pressure?

A

35mmHg

21
Q

What is value osmotic pressure?

A

26-28mmHg

22
Q

Define oncotic pressure?

A

Pressure due to colloids that can’t escape vessel eg proteins

23
Q

Does hydrostatic pressure increase/decrease/stay constant across length glomerular capillary?

A

Constant

24
Q

Does oncotic pressure increase/decrease/stay constant across length glomerular capillary?
Why

A

Increases across length
Proteins more concentrated (not filtered)
20% higher

25
Q

What is equation GFR?

A

GFR= Hydrostatic pressure-oncotic pressure

26
Q

At end of glomerular capillaries what is balance hydrostatic and oncotic pressure?

A

Eqbm

27
Q

Explain water movement in and out capillaries

A
28
Q

Does oncotic pressure bring water in or out?

A

In
Plasma proteins create gradient water diffuses across

29
Q

Is pressure higher on arterial end of capillary bed or venule?
Figures?

A

Arterial- 30mmHg
Venule- 20mmHg

30
Q

Where does exchange occur?
What is exchanged?
Where does move?

A

Capillary bed
Oxygen, glucose, ions, hormones
From capillary bed into interstitial space

31
Q

Explain how water and ions leave and BP is maintained?

A

1) Arterial pressure pushes out water and ions etc in IF
2) Plasma proteins too big leave capillary bed
3) Plasma protein increased @venule end
4) Plasma proteins create low water conc (high solutes)
Colloid osmotic pressure
5) Draw water back capillary bed
6) Maintain BP

32
Q

Is pressure higher at arterial or venule end?

A

Arterial

33
Q

Are proteins in glomerular filtrate?

A

No

34
Q

Define ultrafiltrate?

A

Contain virtually all substances found in plasma in similar concentrations
No large prteins?

35
Q

What is present in filtrate? (4 examples)
What size can pass?

A

Small molecules and ions- 10 kDa or smaller
1) Glucose
2) Uric acid
3) K+
4) Creatinine

36
Q

Why is albumin not filtered?

A

Negatively charged glomerular bm repels negative ions

37
Q

Is glucose filtered?

A

Yes

38
Q

What is only protein found urine (filtered)?

A

Tamm– Horsfall protein (uromodulin)

39
Q

Why is lack of protein in urine of clinical relevance?

A

Protein not normally found urine
If protein in urine indicate damage to filtration barrier- protein link
Diabetes

40
Q

State the equation for filtration fraction?

A

Filtration Fraction = GFR / Renal Plasma Flow
Proportion filtered

41
Q

What is rate of renal blood flow?
What is renal plasma flow?
Filtration fraction?

A

1mL/min
40% cells
60% plasma

600ml/min
Filtration Fraction = 125/600 = ~0.2%

42
Q

What is value filtration fraction?

A

0.2%

43
Q

What is urine output value?

A

Urine output = 0.5ml/kg/h

44
Q

Define renal clearance?
Equation

A

Volume of plasma from which a substance is completely removed from the kidney per unit time

Clearance = (urine concentration x urine volume) / plasma concentration

45
Q

What is renal clearance of creatine?

A

125ml/min
Equal GFR

46
Q

Is creatine filtered at glomerulus?

A

Yes

47
Q

Is creatine absorbed or secreted in tubule?
Where end up?

A

No
Urine

48
Q

What is used measure GFR?
Why?

A

Creatine
Not absorbed or secreted tubule

Kidney (11 decks)

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