Author Question: A cell is isolated, and electrophysiology studies reveal that the resting membrane potential is 70 ... (Read 105 times)

chads108 · **on:** Jun 25, 2018

A cell is isolated, and electrophysiology studies reveal that the resting membrane potential is 70 mV. The predominant intracellular ion is Na+, and the predominant extracellular ion is K+.

With voltage change, which of the following would result in an action potential?
a. K+ rushing into the cell
b. Na+ rushing into the cell
c. Na+ rushing out of the cell
d. K+ rushing out of the cell

Question 2

What is the role of cytokines in cell reproduction?

a. Provide growth factor for tissue growth and development.
b. Block progress of cell reproduction through the cell cycle.
c. Restrain cell growth and development.
d. Provide nutrients for cell growth and de-velopment.

Toya9913 · **Reply #1 on:** Jun 25, 2018

Answer to Question 1

ANS: A
With voltage change, potassium rushes into, not out of, the cell. Sodium movement is not related to this process.

Answer to Question 2

ANS: A
Cytokines play a major role in the regulation of tissue growth and development but do not re-strain it. Cytokines help overcome intracellular braking mechanisms that restrain cell growth and promote cell growth, but they do not provide nutrients.