Question

What is the function of the sodium-calcium exchanger in cardiac muscle?

A) depolarize the cell
B) trigger the release of calcium from the sarcoplasmic reticulum
C) remove calcium from the cytosol by transporting it to the extracellular fluid
D) remove calcium from the cytosol by transporting it into the sarcoplasmic reticulum
E) interact with troponin to initiate cross-bridge cycling

Answer 1

The sodium-calcium exchanger in cardiac muscle removes calcium from the cytosol by transporting it to the extracellular fluid, helping regulate muscle contraction.

Step-by-step explanation:

The function of the sodium-calcium exchanger in cardiac muscle is to remove calcium from the cytosol by transporting it to the extracellular fluid. Therefore, the correct answer is C) remove calcium from the cytosol by transporting it to the extracellular fluid.

The sodium-calcium exchanger is classified as secondary active transport because it uses the energy stored in the sodium gradient to transport calcium against its concentration gradient.

This process helps regulate the calcium concentration within the cytosol, allowing for proper muscle contraction and relaxation.