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Flashcards in 2nd Exam Deck (95)
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1
Q

What artery carries blood to the kidneys?

A

Renal Artery

2
Q

What 2 structures make up the renal corpuscle?

A

Glomerulus & Bowman’s Capsule

3
Q

What structure brings blood to the renal corpuscle?

A

Afferent arteriole

4
Q

What’s not filtered out in the formation of urine?

A

Red blood cells

Plasma proteins

5
Q

How does the body regulate pressure to the renal corpuscle?

A

Smooth muscle of afferent and efferent arterioles

6
Q

What is RPF?

A

Renal Plasma Flow; vol of blood plasma delivered to the kidneys per unit time

7
Q

What is FF?

A

Filtration Fraction; proportion of fluid reaching the kidneys which passes into the renal tubules

8
Q

What is the typical filtration fraction? Renal plasma flow?

A
FF= 20%
RPF= 550 ml/min
9
Q

RPFxFF=what?

A

GFR; glomerular filtration rate

10
Q

Contracting the efferent arteriole would alter which factor: RPF or FF?

A

FF, would increase glomerular pressure

11
Q

What are the 2 methods of altering RPF?

A

Increase cardiac output, dilate afferent arteriole

12
Q

T/F: Fenestrae are small pores and slit pores are larger pores.

A

False: Fenestrae=large, slit pores=small

13
Q

T/F: Excretion rates are less than filtration rates for most electrolytes like sodium, chloride, and bicarbonate.

A

True

14
Q

T/F: Amino acids and glucose are completely reabsorbed from the tubules under normal conditions.

A

True

15
Q

When excretion rate=filtration rate + secretion rate, what does this mean?

A

Solute is being excreted in large amounts in the urine, ex: drugs, organic acids & bases

16
Q

What is the capillary filtration coefficient? (Kf)

A

Measure of permeability and surface area of the glomerular capillary

17
Q

Normally functioning adults should have a ___ glomerular hydrostatic pressure, and a ___ filtration coefficient.

A

High glom HP, Large filtration coefficient

18
Q

What is unique about the layers of the glomerular capillary membrane?

A

3 layers instead of normal 2; (endothelium, basement membrane, and epithelial layer of podocytes)

19
Q

T/F: The positive charge of plasma proteins prevents it from exiting the glomerular capillary.

A

False: plasma proteins are negatively charged

20
Q

The filtration barrier of glomerular capillary membrane is highly dependent on molecule __ and ____ ____.

A

molecule size and electrical charge

21
Q

Albumin becomes filtered and is appearing in the urine, what is the likely cause?

A

Basement membrane lost it’s negative electrical charge and proteins were allowed to be filtered

22
Q

Kf x Net filtration pressure equals what?

A

Kf (capillary filtration coefficient) x Net Filtration Pressure= Glomerular Filtration Rate (GFR)

23
Q

What are the 4 determining pressures of GFR?

A
  1. Hydrostatic Pressure of Glomerular Capillaries
  2. HP of Bowman’s Capsule
  3. Colloid Osmotic Pressure of Glom. Capillaries
  4. COP of proteins in Bowman’s Capsule
24
Q

What pressure should be 0 if the body’s working properly?

A

Bowman’s Capsule Osmotic Pressure

25
Q

T/F: Osmotic pressure can also be called oncotic pressure.

A

True

26
Q

Name 2 things that would decrease Kf thus decrease GFR?

A
  1. Decr amt of functioning glomerular capillaries

2. Incr thickness of capillaries

27
Q

What happens to the GFR if you were to increase the pressure in the Bowman’s capsule?

A

Decr. GFR

28
Q

T/F: If you incr. the glomerular colloid osmotic pressure, it would decr. the GFR.

A

True

29
Q

When glomerular hydrostatic pressure is __, it promotes filtration and thus increases GFR.

A

Increased

30
Q

T/F: If you dilate the afferent arteriole, glomerular capillary hydrostatic pressure increases.

A

True

31
Q

What two things happen when you constrict the efferent arteriole?

A

Glomerular capillary hydrostatic pressure increases,

Glomerular Filtration Rate increases.

32
Q

T/F: Manipulating the efferent arteriole is just as efficient as manipulating the afferent arteriole when it comes to changing GFR.

A

False: Manipulating AFFERENT much more effective, than manipulating efferent.

33
Q

Where are the 3 places renal vascular resistance occurs?

A

Interlobular arteries
Afferent arterioles
Efferent arterioles

34
Q

T/F: The renal cortex receives most of the blood flow into the kidney whereas the renal medulla only receives about 1-2%.

A

True

35
Q

Sympathetic NS stimulation (and its hormones like epinephrine and norepinephrine) would have what effect of GFR?

A

Decreases GFR; try to hold onto our fluid

36
Q

Endothelin is a vasoconstrictor released in response to injury, what would it do to GFR?

A

Decrease GFR

37
Q

What 3 vasodilators would increase renal blood flow and increase GFR?

A
  1. Prostaglandins
  2. Bradykinin
  3. Endothelial-derived nitric oxide
38
Q

What is the myogenic mechanism & what is it’s purpose?

A

Ability of individual blood vessels to resist stretching during increased arterial pressure;
Protects kidneys from damage during incr. BP

39
Q

Glomerular Filtration - Tubular Reabsorption + Tubular Secretion = what?

A

Urine formation

40
Q

What is the most vital aspect of determining excretion rate?

A

Tubular reabsorption

41
Q

T/F: Tubular reabsorption is highly selective and glomerular filtration is non-selective.

A

True

42
Q

T/F: Tubular reabsorption is both an active and passive process.

A

True

43
Q

What is ultrafiltration?

A

Water and solutes moving in bulk flow thru the peritubular capillary wall into the blood

44
Q

What are the 2 types of active transport?

A

Primary-coupled w/ hydrolysis of ATP

Secondary-coupled indirectly to the energy source

45
Q

Na-K ATPase pump is an example of which active transport: primary or secondary?

A

Primary

46
Q

T/F: Water is always absorbed via the passive mechanism called osmosis.

A

True

47
Q

Sodium Glucose co-transporters (SGLT1 & SGLT2) are located where?

A

SGLT2-early part of proximal tubule (90% of glucose reabsorption)
SGLT1-later part of proximal tubule (remaining 10%)

48
Q

What is a transport maximum?

A

The limit to the rate at which a solute can be transported during active reabsorption or secretion.

49
Q

T/F: Sodium and glucose do not have transport maximums.

A

False: Sodium does NOT.

Glucose does!

50
Q

T/F: Sodium transport in the proximal tubules obey gradient time transport principles.

A

True (meaning higher concentration of Na, more reabsorption or slower flow rate–>more Na reabsorbed.)

51
Q

T/F: Almost all creatinine filtered at the glomerulus is excreted.

A

True

52
Q

Where is the majority of water and sodium reabsorbed: Proximal tubule, Descending limb, Ascending limb, or Distal tubule?

A

Proximal Tubule (65% reabsorbed)

53
Q

What 4 things are rapidly reabsorbed in the first half of the proximal tubule?

A

Sodium, glucose, amino acids, water

54
Q

What sort of things are secreted into the tubules?

A

Organic acids & bases, drugs, toxins

55
Q

What are the 3 parts of the Loop of Henle?

A
  1. Thin descending limb
  2. Thin ascending segment
  3. Thick ascending segment
56
Q

20% of water is reabsorbed in what part of the Loop of Henle?

A

Thin descending limb

57
Q

What is occurring in the thick ascending segment of the Loop of Henle?

A

Active reabsorption of Na, Cl, & K

58
Q

The Na-H counter-transport mechanism is found where and what does it do?

A

Thick ascending segment; sodium reabsorbed and hydrogen secreted.

59
Q

Which part of the Loop of Henle is impermeable to water?

A

Thick ascending segment, (concentrates the urine as needed)

60
Q

How is the distal tubule divided?

A

First portion=macula densa

Next part=diluting segment

61
Q

What two things is the diluting segment of the distal tubule impermeable to?

A

Water & Urea

62
Q

Calcium, bicarbonate and magnesium are absorbed in the __ ___ limb in the Loop of Henle.

A

Thick Ascending

63
Q

What 2 cells are found in the late distal tubule and cortical collecting duct?

A

Principal cells & Intercalated cells

64
Q

Principal cells are responsible for __ reabsorption and __ secretion.

A

Na reabsorption, K secretion

65
Q

What is the responsibility of intercalated cells?

A

H secretion, bicarbonate and K reabsorption

66
Q

What hormone controls the reabsorption of Na and the secretion of K?

A

Aldosterone

67
Q

Regarding the late distal tubule and cortical collecting duct, high ADH leads to a __ permeability to water.

A

high

68
Q

What 2 substances may be reabsorbed in the medullary collecting duct that is responsible for urine concentration?

A

Water, Urea

69
Q

Without ADH, we would excrete ___ quantities of ___ urine.

A

…large quantities of dilute urine.

70
Q

Where is aldosterone secreted from?

A

Zona glomerulosa cells of the adrenal cortex

71
Q

Incr extracellular K concentration–> __ angiotensin II levels, which leads to aldosterone being released.

A

Incr.

72
Q

What is the function of ADH/vasopressin?

A

Conserve water by increasing water permeability in distal tubule and collecting duct

73
Q

T/F: ANP inhibits reabsorption of water and sodium, increasing urinary excretion and lowering blood volume (thus lowering BP).

A

True

74
Q

What effect does PTH have on tubular reabsorption?

A

Increases Ca reabsorption (Loop of Henle, Distal tubule)
Inhibit phosphate reabsorption (proximal tubule)
Increases Mg reabsorption (Loop of Henle)

75
Q

Is angiotensin II present when there is high or low BP?

A

Low, increases Na and water reabsorption

76
Q

Angiotensin II has what effect on efferent arterioles?

A

Constricts

77
Q

The rate of what hormone secretion determines whether the kidneys excrete dilute or concentrated urine?

A

ADH

78
Q

T/F: Osmolarity is held constant throughout the proximal tubule.

A

True

79
Q

Which segment of the Loop of Henle is not permeable to water?

A

Thick ascending limb

80
Q

Where does the change in osmolarity occur?

A

Leaving the Loop of Henle (goes from 300 mOsm/L to 200 mOsm/L)

81
Q

What test is used to assess the concentration of urine?

A

Urine Specific Gravity Test

82
Q

What does a high specific gravity indicate?

A

High concentration of urine

83
Q

T/F: The range for a specific gravity test is about 1.002-1.028 g/ml.

A

True

84
Q

What are the 2 basic requirements for forming a concentrated urine?

A
  1. High level of ADH

2. High osmolarity of the renal medullary interstitial fluid

85
Q

What is the countercurrent mechanism useful for?

A

Creating a hyperosmotic renal medullary interstitial fluid

86
Q

Osmoreceptor cells in the ___ ___ shrink causing it to fire and stimulate the __ pituitary to release ADH.

A

anterior hypothalamus, posterior

87
Q

ADH affects which 3 areas to become more permeable to water?

A

Late distal tubule
Cortical collecting tubules
Medullary collecting ducts

88
Q

What is the anteroventral region of the 3rd ventricle also referred to as?

A

AV3V region

89
Q

What are cells in the AV3V region stimulated by?

A

Stimulated by a small increase in extracellular fluid osmolarity

90
Q

A decrease in arterial pressure causes a(n) ___ in ADH.

A

increase

91
Q

T/F: Nausea, hypoxia, and drugs all decrease ADH secretion.

A

False: …increase ADH secretion

92
Q

Is alcohol an inhibitor of ADH secretion?

A

Yep

93
Q

Decreased blood volume and decreased BP has what effect on thirst?

A

Increases thirst

94
Q

T/F: Gastric distention decreases thirst.

A

True

95
Q

What is the obligatory urine volume loss?

A

The amount of urine that needs to be excreted in order to rid the body of waste products.