Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Step 2 in the above figure is accomplished by: a. an efflux of Ca2+. b. an efflu

ID: 166696 • Letter: S

Question

Step 2 in the above figure is accomplished by: a. an efflux of Ca2+. b. an efflux of Na+. c. an efflux of K+. d. an influx of Na+. e. an influx of K+. Step 3 in the above figure is accomplished by: a. an efflux of Ca2+. b. an efflux of Na+. c an efflux of K+. d. an influx of Na+. e. an influx of K+. In the above figure, the lower dashed line is: a. the resting state. b. indicative of repolarization. c. the threshold level for opening Na+ channels. d. the equilibrium potential. e. indicative of hyperpolarization. In the above figure, the upper dashed line is: a. the resting state. b. indicative of repolarization. c. the threshold level for opening Na+ channels. d. the equilibrium potential. e. indicative of hyperpolarizations.

Explanation / Answer

1. The step 2 in the above curve is depolarization. It occurs due to influx of Na+ ions. Although it can be mediated by an influx of any kind of cation or efflux of any kind of anion. Option d is the correct answer.

2. Step 3 represents repolarization. It is opposite of depolarization. This is accomplished by efflux of K+ ions. Option c is the correct answer.

3. Option A is the correct answer. The lower dashed line represents the resting state of the membrane.

4. The correct answer is option c. The upper dashed line represents the threshold value.