L7: Potassuim Flashcards
1. What is the main intracellular cation?
- a. Sodium
- b. Potassium
- c. Calcium
- d. Magnesium
B
2. What is the effect of increased plasma K+ on excitability?
- a. Hyperexcitability
- b. Hypoexcitability
- c. No change in excitability
- d. Decreased osmolarity
A
3. What can cause increased plasma K+ levels?
- a. Acid-base disbalance (metabolic acidosis)
- b. Plasma osmolarity
- c. Alkaline pH
- d. Hydration
A
4. What happens in hypertonic plasma regarding cell osmolarity?
- a. Decreases osmolarity in the cell
- b. Increases osmolarity in the cell
- c. No effect on cell osmolarity
- d. Causes cell lysis
B
5. What does hypokalemia result in?
- a. Increased membrane potential
- b. Decreased excitability
- c. Hyperkalemia
- d. Cell lysis
B
6. Which tissues are highly affected by changes in potassium levels?
- a. Skeletal muscle
- b. Brain
- c. Heart
- d. Liver
C
7. What is the majority of potassium found in?
- a. Extracellular fluid
- b. Blood plasma
- c. Intracellular fluid
- d. Interstitial fluid
C
8. How does insulin affect potassium uptake into the cell?
- a. Inhibits K+ uptake
- b. Activates Na/K+ exchanger
- c. Decreases SA node activity
- d. Promotes cell lysis
B
9. How does adrenaline prevent high plasma K+ during exercise?
- a. Inhibits skeletal muscle activity
- b. Stimulates K+ secretion
- c. Increases K+ uptake
- d. Promotes hyperkalemia
C
10. Which factor protects the brain from rapid changes in potassium levels?
- a. Blood-brain barrier
- b. Cerebrospinal fluid
- c. BBB receptors
- d. Neurotransmitters
A
11. What is the clinical significance of IV glucose in hyperkalemia treatment?
- a. Increases potassium secretion
- b. Induces hypokalemia
- c. Promotes potassium uptake into cells
- d. Triggers renal failure
C
12. How does aldosterone respond to long-term hyperkalemia?
- a. Decreases K+ secretion
- b. Activates sodium channels
- c. Increases K+ secretion
- d. Inhibits ENaC
C
13. What is the role of a-Intercalated cells in renal potassium handling?
- a. Promote potassium secretion
- b. Reabsorb potassium
- c. Secrete H+ ions
- d. Activate sodium channels
B
14. How does hyperkalemia affect potassium stores in the cell?
- a. Decreases intracellular potassium
- b. Causes intracellular hyperkalemia
- c. Has no impact on intracellular stores
- d. Promotes potassium excretion
B
15. What stimulates aldosterone release for potassium regulation?
- a. Low plasma sodium
- b. Low blood volume
- c. Hyperkalemia
- d. High plasma osmolarity
C
16. How does ADH affect sodium reabsorption and potassium secretion?
- a. Increases both sodium reabsorption and potassium secretion
- b. Inhibits both sodium reabsorption and potassium secretion
- c. Increases sodium reabsorption, inhibits potassium secretion
- d. Has no effect on renal ion handling
C
17. What factor does not change potassium levels?
- a. Body water content
- b. Diuretics use
- c. Increased tubular fluid flow
- d. Hypovolemia
C
18. How does hypovolemia affect potassium handling in the kidneys?
- a. Increases K+ reabsorption
- b. Decreases K+ secretion
- c. Has no effect on K+ handling
- d. Promotes K+ excretion
C
19. What is the effect of high sodium intake on potassium levels?
- a. Increases K+ secretion
- b. Decreases K+ reabsorption
- c. Decreases K+ levels
- d. Has no impact on K+ regulation
C
20. How does flow rate affect potassium excretion through cilia?
- a. Decreases K+ excretion
- b. Promotes K+ secretion
- c. Has no effect on K+ excretion
- d. Induces hyperkalemia
C
21. What is the primary mechanism of potassium reabsorption in the PCT (Proximal Convoluted Tubule)?
- a. Filtration
- b. Active transport
- c. Solvent drag
- d. Facilitated diffusion
C
22. How is potassium reabsorbed in the TALH (Thick Ascending Limb of Henle)?
- a. Via Na/K pump
- b. Passive diffusion
- c. NKCC cotransporter
- d. Through aquaporins
C
23. Which cells in the DCT (Distal Convoluted Tubule) and CT (Collecting Tubule) are involved in potassium reabsorption?
- a. Principle cells
- b. Intercalated cells
- c. Endothelial cells
- d. Epithelial cells
B
24. What is the impact of renal failure on potassium secretion?
- a. Increases K+ secretion
- b. Enhances K+ reabsorption
- c. Impairs K+ secretion
- d. Promotes intracellular hyperkalemia
C
25. How does aldosterone respond to increased potassium levels?
- a. Inhibits K+ secretion
- b. Activates NKCC cotransporter
- c. Increases K+ secretion
- d. Promotes potassium excretion
C
26. What is the role of ADH (Antidiuretic Hormone) in sodium and potassium handling?
- a. Increases both sodium reabsorption and potassium secretion
- b. Inhibits both sodium reabsorption and potassium secretion
- c. Increases sodium reabsorption, inhibits potassium secretion
- d. Promotes sodium excretion, increases potassium secretion
C
27. Which factor does not influence potassium levels?
- a. Body water content
- b. Diuretics use
- c. Increased tubular fluid flow
- d. Hypovolemia
Cc
28. How does high flow rate impact potassium excretion through cilia?
- a. Decreases K+ excretion
- b. Promotes K+ secretion
- c. Has no effect on K+ excretion
- d. Induces hyperkalemia
C
29. What is the clinical significance of hyperkalemia adaptation in individuals exposed to elevated potassium levels?
- a. Increases K+ secretion
- b. Enhances potassium reabsorption
- c. Adapts to higher K+ levels
- d. Promotes intracellular hyperkalemia
C
30. How do diuretics impact potassium homeostasis?
- a. Increase K+ secretion
- b. Decrease K+ reabsorption
- c. Induce hyperkalemia
- d. Have no effect on K+ regulation
C
31. What is the role of aldosterone in response to long-term hyperkalemia?
- a. Decreases K+ secretion
- b. Activates sodium channels
- c. Increases K+ secretion
- d. Inhibits ENaC
C
32. How does ADH (Antidiuretic Hormone) affect sodium and potassium handling in the kidneys?
- a. Increases both sodium reabsorption and potassium secretion
- b. Inhibits both sodium reabsorption and potassium secretion
- c. Increases sodium reabsorption, inhibits potassium secretion
- d. Promotes sodium excretion, increases potassium secretion
C
33. Which cells in the renal tubules are involved in reabsorbing potassium through H/K ATPase?
- a. Principal cells
- b. Intercalated cells
- c. Endothelial cells
- d. Epithelial cells
B
34. What is the effect of insulin on potassium uptake into cells?
- a. Inhibits K+ uptake
- b. Activates Na/K+ exchanger
- c. Decreases SA node activity
- d. Promotes cell lysis
B
35. How does high sodium intake impact potassium levels?
- a. Increases K+ secretion
- b. Decreases K+ reabsorption
- c. Decreases K+ levels
- d. Has no impact on K+ regulation
C
36. What stimulates aldosterone release for potassium regulation?
- a. Low plasma sodium
- b. Low blood volume
- c. Hyperkalemia
- d. High plasma osmolarity
C
- What is the clinical significance of hyperkalemia adaptation in individuals exposed to elevated potassium levels?**
- a. Increases K+ secretion
- b. Enhances potassium reabsorption
- c. Adapts to higher K+ levels
- d. Promotes intracellular hyperkalemia
C
*38. What happens in hypertonic plasma regarding cell osmolarity?**
- a. Decreases osmolarity in the cell
- b. Increases osmolarity in the cell
- c. No effect on cell osmolarity
- d. Causes cell lysis
B
39. How does adrenaline prevent high plasma K+ during exercise?
- a. Inhibits skeletal muscle activity
- b. Stimulates K+ secretion
- c. Increases K+ uptake
- d. Promotes hyperkalemia
C
*40. What is the clinical significance of IV glucose in hyperkalemia treatment?**
- a. Increases potassium secretion
- b. Induces hypokalemia
- c. Promotes potassium uptake into cells
- d. Triggers renal failure
C
41. How does acid-base imbalance contribute to increased plasma K+?
- a. Decreases K+ levels
- b. Increases K+ levels
- c. Has no effect on K+
- d. Promotes intracellular hyperkalemia
B
42. In hypertonic plasma, what happens to cell osmolarity and K+ movement?
- a. Decreases osmolarity; K+ moves into the cell
- b. Increases osmolarity; K+ moves into the cell
- c. No effect on osmolarity; K+ moves out of the cell
- d. Causes cell lysis; K+ remains unchanged
B
43. What is the primary effect of insulin on potassium uptake?
- a. Inhibits potassium uptake
- b. Activates Na/K+ exchanger
- c. Promotes cell lysis
- d. Increases SA node activity
B
44. How does increased flow rate impact potassium excretion through cilia?
- a. Decreases K+ excretion
- b. Promotes K+ secretion
- c. Has no effect on K+ excretion
- d. Induces hyperkalemia
C
45. What tissues are highly affected by changes in potassium levels?
- a. Skeletal muscle and liver
- b. Heart and brain
- c. Kidneys and lungs
- d. Skin and pancreas
B
46. What is the major intracellular cation?
- a. Sodium
- b. Potassium
- c. Calcium
- d. Magnesium
B
47. How does hypovolemia impact potassium handling in the kidneys?
- a. Increases K+ secretion
- b. Decreases K+ reabsorption
- c. Has no effect on K+ handling
- d. Promotes K+ excretion
C
48. What is the role of ADH in potassium secretion?
- a. Inhibits potassium secretion
- b. Activates sodium channels
- c. Stimulates potassium secretion
- d. Promotes intracellular hyperkalemia
C
49. How does hyperkalemia impact intracellular potassium levels?
- a. Decreases intracellular potassium
- b. Causes intracellular hyperkalemia
- c. Has no impact on intracellular stores
- d. Promotes potassium excretion
B
50. What is the primary factor affecting potassium homeostasis during diuresis?
- a. Decreased ADH levels
- b. Increased sodium reabsorption
- c. Potassium reabsorption
- d. Hyperkalemia induction
C
51. How does increased cilia bending impact potassium excretion through the renal tubules?
- a. Decreases K+ excretion
- b. Promotes K+ secretion
- c. Has no effect on K+ excretion
- d. Induces hyperkalemia
C
52. What is the primary role of BK (Maxi) channels in potassium secretion?
- a. Flow-dependent secretion
- b. Constitutive secretion
- c. Sequestered secretion
- d. Sodium reabsorption
C
53. What stimulates the opening of BK channels in the renal tubules?
- a. Increased sodium levels
- b. Calcium entry or partial depolarization
- c. Decreased flow rate
- d. Inhibition by aldosterone
B
54. How does hypokalemia affect membrane potential and cell excitability?
- a. Increases membrane potential
- b. Decreases excitability
- c. Has no impact on membrane potential
- d. Promotes hyperexcitability
B
55. What is the main effect of increased sodium intake on potassium levels?
- a. Increases K+ secretion
- b. Decreases K+ reabsorption
- c. Decreases K+ levels
- d. Has no impact on K+ regulation
C
56. How does increased tubular fluid flow affect potassium handling in the renal tubules?
- a. Increases K+ secretion
- b. Decreases K+ reabsorption
- c. Has no effect on K+ handling
- d. Promotes K+ excretion
C
57. What stimulates aldosterone release to regulate potassium levels?
- a. Low plasma sodium
- b. Low blood volume
- c. Hyperkalemia (Answer)
- d. High plasma osmolarity
C
58. How does insulin impact potassium uptake into cells?
- a. Inhibits potassium uptake
- b. Activates Na/K+ exchanger
- c. Decreases SA node activity
- d. Promotes cell lysis
B
59. What tissues are less affected by changes in potassium levels?
- a. Heart and brain
- b. Skeletal muscle and liver
- c. Skeletal muscle and lungs
- d. Skeletal muscle and kidneys
D
60. What is the primary mechanism of potassium reabsorption in the PCT (Proximal Convoluted Tubule)?
- a. Filtration
- b. Active transport
- c. Solvent drag
- d. Facilitated diffusion
C
