Depolarization occurs when which two electrolytes rush into the ...

[biggirl4568]

Depolarization occurs when which two electrolytes rush into the cell?
 
  1. Sodium and potassium
  2. Calcium and magnesium
  3. Calcium and sodium
  4. Chloride and potassium

Question 2

In a person with a sinus rhythm, the primary purpose of the AV node is to
 
  1. pace the heart at 4060 bpm.
  2. delay the impulse from the SA node.
  3. pace the heart at 60100 bpm.
  4. inhibit the impulse from the SA node.

[KKcool]

Answer to Question 1

Correct Answer: 3
Rationale: An action potential begins when sodium and calcium flow into the cell, resulting in depolarization.

Answer to Question 2

Correct Answer: 2
Rationale: The AV node delays the impulse as it travels from the atria to the ventricles. The AV junction does pace the heart at 4060 bpm, but not when the SA node is pacing the heart.

[biggirl4568]

Gracias!

[cpetit11]

Excellent