Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

ANS 433: Neural, Muscular, Renal Physiology > Kidney Pt. 2 > Flashcards

Kidney Pt. 2 Flashcards

1
Q

When does kidney dysfunction become apparent?

A

When the kidney is at <25% of normal functionality.

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

What happens when one kidney starts to fail?

A
  1. The remaining nephrons in that kidney adapt to handle the larger than normal load.
  2. The other kidney will take on more of the filtration load.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What happens when one kidney is surgically removed?

A

The remaining kidney hypertrophies to filter blood at 80% of the rate of 2 kidneys.

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

What are the 3 basic functions of the nephron?

A
  1. Glomerular filtration.
  2. Tubular reabsorption.
  3. Tubular secretion.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What occurs during glomerular filtration?

A

Water and most solutes in the blood plasma move across the wall of the glomerular capillaries into the glomerular capsule and into the renal tubule.

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

What occurs during tubular reabsorption?

A

The filtered fluid flows along the renal tubule and through collecting ducts as ~99% of filtered water and useful solutes are reabsorbed by tubule cells.

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

How does reabsorbed water and solutes return to the main blood supply?

A

Peritubular capillaries and vasa recta.

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

What occurs during tubular secretion?

A

Fluid flows through renal tubules and through collecting ducts, the tubule and duct cells secrete waste, drugs, and excess ions into the filtered fluid.

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

What is the fluid that enters the capsular space called?

A

Glomerular filtrate.

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

What is the daily volume of glomerular filtrate in adult females?

A

150 L.

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

What is the daily volume of glomerular filtrate in adult males?

A

180 L.

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

How many liters of urine are excreted by the average adult daily?

A

1-2 liters.

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

What are the 3 barriers that substances filtered in the glomerulus must cross?

A
  1. Glomerular endothelial cells.
  2. Basal lamina.
  3. Filtration slits formed by podocytes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the filtration membrane described as?

A

A leaky barrier.

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

What is the filtration membrane composed of?

A
  1. Endothelial cells of glomerular capillaries.
  2. Podocytes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does glomerular filtration permit filtration of?

A
  1. Small solutes.
  2. Water.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does glomerular filtration prevent filtration of?

A
  1. Blood cells.
  2. Plasma proteins.
  3. Platelets.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do glomerular endothelial cells contain?

A

Fenestrations/large pores.

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

What do these fenestrations permit?

A

All solutes in the blood plasma to exit glomerular capillaries with the exception of blood cells and platelets.

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

What are mesangial cells and what is their function?

A

Contractile cells that help regulate filtration.

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

Where are mesangial cells located?

A
  1. Among the glomerular capillaries.
  2. In the cleft between afferent and efferent arterioles.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the basal lamina and what is its function?

A

The layer of material between endothelium and podocytes in the glomerulus that prevents filtration of larger plasma proteins.

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

What is the basal lamina composed of?

A
  1. Minute collagen fibers.
  2. Proteoglycan.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are filtration slits and what is their function?

A

The spaces between pedicels covered by slit membranes that permit the passage of smaller diameter molecules.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What molecules pass through the filtration slits and slit membranes?
1. AA's. 2. Ammonia. 3. Ions. 4. Glucose. 5. Urea. 6. Very small plasma proteins. 7. Vitamins. 8. Water.
26
What are the 3 main pressures that contribute to net filtration pressure?
1. Glomerular blood hydrostatic pressure (GBHP). 2. Capsular hydrostatic pressure (CHP). 3. Blood colloid osmotic pressure (BCOP).
27
Which type(s) of pressure promotes filtration?
GBHP.
28
Which type(s) of pressure oppose filtration?
1. CHP. 2. BCOP.
29
What is GBHP?
The blood pressure in glomerular capillaries the promotes filtration by forcing water and solutes in blood plasma through the filtration membrane.
30
What is the GBHP in mmHg?
~55.
31
What is CHP?
The hydrostatic pressure exerted against the filtration membrane by fluids already in the capsular spaces and renal tubules. A form of "back pressure".
32
What is the CHP in mmHg?
~15.
33
What is BCOP?
The pressure exerted as a result of proteins in the blood plasma attracting fluid back into the blood.
34
What is BCOP in mmHg?
~30.
35
How is net filtration pressure (NFP) calculated?
NFP= GBHP-CHP-BCOP.
36
What is the NFP of a normal kidney?
10 mmHg promoting filtration.
37
What is the amount of filtrate formed in all renal corpuscles in both kidneys each minute in females?
125 mL.
38
What is the amount of filtrate formed in all renal corpuscles in both kidneys each minute in males?
105 mL.
39
Is GFR relatively constant?
Yes.
40
What occurs is GFR is too high?
Substances pass to quickly through the renal tubules and may not be reabsorbed properly.
41
What occurs if GFR is too low?
Nearly all the filtrate is reabsorbed and the waste products may not be properly excreted.
42
What is GFR related to?
The pressures that determine net filtration pressure. ex: Severe blood loss leading to decreased arterial blood pressure leads the GBHP to be less than or equal to 45 mmHg, stopping filtration entirely.
43
What are the 2 main ways that the GFR is regulated?
1. Adjusting blood flow into/ out of the glomerulus. 2. Altering glomerular capillary surface area available for filtration.
44
What are the 3 mechanisms that control GFR?
1. Renal autoregulation. 2. Neural regulation. 3. Hormonal regulation.
45
What occurs during renal autoregulation?
The kidneys help maintain a constant renal blood flow through the myogenic mechanism and tubuloglomerular feedback.
46
What is the myogenic mechanism?
The mechanisms that causes the contraction and relaxation of smooth muscle cells in the walls of the afferent arterioles in response to stretching.
47
When blood pressure rises in response to the myogenic mechanism, what increases?
GFR in response to increased in renal blood flow.
48
What does increased renal blood flow and blood pressure cause to occur?
Stretching of the walls of the afferent arterioles, triggering a contraction of the smooth muscle cells in the walls of those blood vessels.
49
What dos the contraction of smooth muscles in the afferent arterioles cause?
Decreased renal blood flow and GFR.
50
How long does it take for the myogenic mechanisms to normalize renal blood flow and GFR?
Seconds.
51
What is tubuloglomerular feedback?
The macula densa providing feedback to the glomerulus due to elevated systemic blood pressure.
52
What does tubuloglomerular feedback cause to occur in the renal tubules?
Filtered fluid to flow more rapidly.
53
What is given less time to be absorbed in the PCT and LOH due to tubuloglomerular feedback?
1. Cl-, 2. Na+. 3. Water.
54
What is inhibited in JGA cells when macula densa cells detect increased delivery?
The release of NO.
55
What does NO cause?
Vasodilation.
56
How fast is the feedback loop for tubuloglomerular feedback
Slower than the myogenic mechanism.
57
What are the renal blood vessels innervated by?
Sympathetic ANS nerve fibers.
58
What neurotransmitter do the nerve fibers innervating the renal blood vessels release?
Norepinephrine.
59
What does norepinephrine cause in renal blood vessels?
Vasoconstriction through targeting a1 receptors. *Plentiful in smooth muscles of afferent arterioles.
60
What does the neural regulation of the renal blood flow look like at rest?
1. Sympathetic stimulation is low, so the arterioles are dilated. 2. Autoregulation of GFR prevails.
61
How do afferent and efferent arterioles constrict under moderate sympathetic stimulation?
The same extent, restricting blood flow to the same extent in each.
62
How do afferent and efferent arterioles constrict under greater sympathetic stimulation?
Vasoconstriction of the afferent arterioles is predominant.
63
What happens with lower renal blood flow?
1. Reduced urine output to conserve blood volume and allow it to flow to other body tissues.
64
What affect does angiotensin II have on the kidneys?
Reduces GFR.
65
What affect does angiotensin II have on blood vessels?
Very potent vasoconstrictor.
66
What affect does atrial natriuretic peptide (ANP) have on the kidneys?
Increase GFR.
67
What is ANP secreted by?
Cells in the atria of the heart.
68
What affect does ANP have on the kidney?
It causes relaxation of the glomerular mesangial cells, increasing capillary surface area available for filtration, increasing GFR rate.
69
How often does filter fluid enter the PCT?
Every 30 minutes.
70
Is the volume of filter fluid less than or greater than the amount of total blood plasma volume?
Greater than.
71
What portion of the renal tubule makes the largest contribution to reabsorption?
The PCT.
72
What solutes are absorbed during reabsorption?
1. Amino acids. 2. Ca2+. 3. Cl-. 4. Glucose. 5. HCO3-. 6. HPO4-. 7. K+. 8. Na+. 9. Urea.

ANS 433: Neural, Muscular, Renal Physiology (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions