Brainscape's Knowledge GenomeTM

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


See full index

Urinary Tract Physiology > Functional Overview of the Kidneys > Flashcards

Functional Overview of the Kidneys Flashcards

1
Q

What is the primary function of the kidneys?

A

regulate the composition of the extracellular fluid

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

In regulating the composition of extracellular fluid, the kidneys also regulate what 6 things?

A
  1. blood volume
  2. extracellular fluid volume
  3. systemic arterial blood pressure
  4. hematocrit
  5. acid-base balance
  6. plasma concentration of electrolytes, minerals, metabolic waste, and water
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

7 year old beagle question 1:

Plasma sodium is normal (144 meq/L)

Body fluid volume is normal

Dietary sodium intake is 500 mg/day

How much sodium do you expect to appear in the urine every 24 hours?

A. >500 mg

B. 500 mg

C.

A

B. 500 mg

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

7 year old beagle question 2:

Plasma sodium is normal (144 meq/L)

Body fluid volume is normal

Dietary sodium intake is 1500 mg/day

How much sodium do you expect to appear in the urine every 24 hours?

A. >1500 mg

B. 1500 mg

C.

A

B. 1500 mg

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

How do you regulate volume?

A

add or subtract sodium and water will follow

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

How do you regulate tonicity?

A

add or subtract water

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

7 year old beagle question 3:

Plasma sodium is normal (144 meq/L)

Body fluid volume is low

Dietary sodium intake is 500 mg/day

How much sodium do you expect to appear in the urine every 24 hours?

A. >500 mg

B. 500 mg

C.

A

C.

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

7 year old beagle question 4:

Plasma sodium is low (137 meq/L)

Body fluid volume is high

Dietary sodium intake is 500 mg/day

How much sodium do you expect to appear in the urine every 24 hours?

A. >500 mg

B. 500 mg

C.

A

A. >500 mg

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

What happens if protein intake exceeds use and excretion?

A

increased nitrogenous waste in the blood (azotemia)

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

What happens if salt and water intake exceeds use and excretion?

A

ECF volume expansion, increased blood pressure, and/or edema

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

What happens if salt intake is greater than water intake?

A

hypernatremia and decreased ICF volume

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

What happens if water intake is greater than salt intake?

A

hyponatremia and increased ICF volume

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

What are the 3 basic mechanisms of kidney function?

A

filtration reabsorption secretion

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

Energy needs of the kidneys are primarily for which one of the following?

A. Reabsorbing water

B. Excreting waste products

C. Reabsorbing sodium

D. Secreting potassium

E. Secreting hydrogen ions

A

C. Reabsorbing sodium

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

Definition of excretion

A

exit of substances from the body

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

From what point does the urine no longer change in composition?

A

from the renal pelvis to the tip of the urethra

17
Q

Where does filtration occur in the kidneys?

A

glomeruli

18
Q

Where does reabsorption and secretion occur in the kidneys?

A

tubules

19
Q

Definition of glomerular filtration

A

the process by which water and solutes in blood leave the vascular system through the filtration barrier and enter Bowman’s space

20
Q

Definition of reabsorption

A

the process of moving substances from the lumen across the epithelial layer into the surrounding renal interstitium and then on to the bloodstream

21
Q

What are the two steps of reabsorption?

A
  1. removal from the tubular lumen to interstitium 2. movement from interstitium into the blood
22
Q

Definition of secretion

A

the process of moving substances into the tubular lumen from the cytosol of epithelial cells that line the walls of the nephron

23
Q

Determine which picture(s) represent filtration, secretion, and reabsorption

A

Picture 1: secretion

Picture 2: filtration and reabsorption

Picture 3: reabsorption

24
Q

Why are there 2 capillary beds in the kidney?

A

1 capillary bed is for filtration (i.e. goes to the glomerulus)

1 capilary bed is to provide nutrients to the kidney and to reabsorb filtrate from the tubules

25
Q

What type of large substances cannot pass the glomerular filtration barrier?

A

albumin

globulins

cells

26
Q

What happens to protein concentration from one end of the glomerular capillary to the other end?

A

the protein concentration increases, which results in more fluid flow into the capillary

(this is the effect known as “Starlings Forces” and it occurs in the proximal tubules)

27
Q

What is filtration fraction and its equation?

A

Definition: fraction of plasma flowing through the glomerulus that is diverted into Bowman’s space by filtration

FF = GFR/RPF (glomerular filtration rate / renal plasma flow)

28
Q

Which one of the following is correct?

A. As the filtration fraction increases, the Starling forces promoting reabsorption of fluid into the peritubular capillaries increase

B. As the filtration fraction decreases, the Starling forces promoting reabsorption of fluid into the peritubular capillaries increase

A

A. As the filtration fraction increases, the Starling forces promoting reabsorption of fluid into the peritubular capillaries increase

29
Q

What is urine specific gravity?

A

the density of a urine sample versus the density of water

30
Q

What do the following urine specific gravity values mean?

  1. 001
  2. 050
A
  1. 001 = more water than solute
  2. 050 = more solute than water
31
Q

Explain the separation of salt and water in the cortex and medulla

A

cortex - isosmotic with plasma

medulla - progressive hypertonicity

32
Q

What determines if urine is concentrated or diluted?

A

insertion (or not) of aquaporins in the collecting duct

33
Q

What endocrine proteins are made in the kidney?

A

erythropoietin

calcitriol

renin

prostaglandins

34
Q

Characteristics of erythropoietin

A
  • a circulating glycoprotein produced in renal peritubular fibroblast-like type-a interstitial cells
  • released when tissue hypoxia detected
  • causes increased RBC production in bone marrow
35
Q

Characteristics of calcitriol

A
  • most active form of vitamin D
  • produced in the proximal tubules
  • it is a hormone, not a vitamin
  • regulates calcium and phosphate handling as well as cell growth
36
Q

Characteristics of renin

A
  • enzyme secreted by the kidney
  • participates in the renin-angiotensin-aldosterone axis
  • regulates ECF volume and arterial blood pressure
37
Q

What is the final output of the renin-angiotensin-aldosterone axis and what is the purpose?

A

final output is aldosterone release

  • aldosterone causes increased Na+ absorption and increased K+ excretion
38
Q

Where is the kidney innervated (predominantly by alpha-adrenergic sympathetic fibers)?

A

renal arterioles

renal tubular epitehlium

juxtaglomerular apparatus

Urinary Tract Physiology (9 decks)

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