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Flashcards in Urinary System Deck (40)
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1
Q

Definition of glomerular capillary blood pressure

A

the fluid pressure exerted by the blood within the glomerular capillaries

2
Q

Glomerular capillary blood pressure average

A

55 mmHg

3
Q

Glomerular capillary blood pressure:

A

favours filtration

4
Q

Plasma colloid osmotic pressure

A

caused by the unequal distribution of plasma proteins across the glomerular membrane. Opposes filtration.

5
Q

Plasma colloid osmotic pressure average

A

30 mmHg

6
Q

Bowman’s capsule hydrostatic pressure

A

the pressure exerted by the fluid in the initial part of the tubule

7
Q

Bowman’s capsule hydrostatic pressure average

A

15 mmHg

8
Q

Glomerular filtration rate

A

the actual rate of filtration. Depends on the net filtration pressure as well surface area and permeability.

9
Q

GFR average

A

125 mL/min

10
Q

As glomerular capillary blood pressure goes up…

A

the net filtration pressure increases and the GFR increases correspondingly

11
Q

If afferent arteriolar resistance is reduced…

A

more blood flows into the glomerulus and the GFR increases

12
Q

In total, how much Na is reabsorbed?

A

99.5%

13
Q

How much sodium is reabsorbed in the proximal tubule?

A

67%

14
Q

What role does Na reabsorption in the proximal tubule play?

A

Plays role in reabsorbing glucose, amino acids, water, chloride and urea.

15
Q

What percentage of sodium is reabsorbed in the ascending loop of henle?

A

25%

16
Q

what role does sodium reabsorption in the ascending loop of henle play?

A

plays a role in the kidneys ability to produce urine of varying concentration and volume.

17
Q

what percentage of sodium is reabsorbed in the distal and collecting tubules?

A

8%

18
Q

what role does sodium reaborption in the distal and collecting tubules play?

A

plays a role in regulating ECF volume. Is variable and subject to hormonal control.

19
Q

where is K almost completely reabsorbed?

A

in the proximal tublue

20
Q

what percentage of urea is reabsorbed?

A

50%

21
Q

In total, how much water is reabsorbed?

A

99%

22
Q

What percentage of water is passively reabsorbed by the end of the proximal tubule?

A

65%

23
Q

what percentage of water is obligatory reabsorbed from the loop of henle?

A

15%

24
Q

where is the remaining 20% of water reabsorbed?

A

in the distal and collecting tubules. this is subject to hormonal control depending on bodies state of dehydration

25
Q

Filtered load of glucose:

A

125 mg/min

26
Q

Filtered load

A

the quantity of any substance filtered per minute

27
Q

Tubular maximum

A

reached when all carriers for a specific substance are full

28
Q

Tubular maximum for glucose

A

373 mg/min

29
Q

Plasma clearance

A

the volume of plasma completely cleared of that substance by the kidneys

30
Q

plasma clearance of glucose:

A

zero

31
Q

Secretion

A

the transfer of substances from the peritubular capillaries to the tubular lumen

32
Q

H secretion

A

Important in maintaining acid-base balance

can be secreted in the proximal, distal and collecting tubules

33
Q

K secretion

A

keeps plasma concentration at appropriate level to maintain normal membrane excitability. Secreted only in the distal and collecting tubules and is under the control of aldosterone.

34
Q

Organic ion secretion

A

accomplishes more efficient elimination of foreign organic compounds from the body. Secreted only in proximal tubule.

35
Q

Macula densa cells

A

part of autoregulation and the tubuloglomerular feedback. They detect changes in the salt level of the fluid flowing past them.

36
Q

which nephron structure is important in producing urine of varying concentration?

A

loop of henle

37
Q

Blood flowing through the kidneys is _____ % of cardiac output

A

20-25%

38
Q

What occurs after stimulation of the macula densa cells?

A

vasoconstriction of the afferent arteriole

39
Q

Sodium uses ___% of the total energy required by kidney

A

80%

40
Q

Inulin

A

is completely filtered and not reabsorbed or secreted