The sodium-calcium-exchanger (NCX) protein is an antiport protein that is located in the membranes of cardiac muscle cells in humans as well as other cells. Antiport proteins transport two different solutes in opposite directions. The sodium-calcium-exchanger protein functions by secondary active transport and requires the sodium-potassium pump in order to function. The sodium-potassium pump functions by primary active transport and transports sodium ions from the intracellular fluid to the extracellular fluid. • Describe how the sodium-potassium pump provides energy for the function of the sodium-calcium-exchanger. Considering that the NCX protein is an antiport protein, describe the concentration gradient of calcium on both sides of the cell membrane. Describe the direction that the calcium ions are transported.

The sodium-calcium-exchanger (NCX) protein is an antiport protein that is located in the membranes of cardiac muscle cells in humans as well as other cells. Antiport proteins transport two different solutes in opposite directions. The sodium-calcium-exchanger protein functions by secondary active transport and requires the sodium-potassium pump in order to function. The sodium-potassium pump functions by primary active transport and transports sodium ions from the intracellular fluid to the extracellular fluid. • Describe how the sodium-potassium pump provides energy for the function of the sodium-calcium-exchanger. Considering that the NCX protein is an antiport protein, describe the concentration gradient of calcium on both sides of the cell membrane. Describe the direction that the calcium ions are transported.

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter7: The Peripheral Nervous System: Efferent Division

Section: Chapter Questions

Problem 1SQE

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