Question

n animal? Which of the following is most likely true of a protein that cotransports glucose and sodium ions into the intestinal cells of an animal? Sodium ions can move down their electrochemical gradient through the cotransporter whether or not glucose is present outside the cell. Glucose entering the cell down its concentration gradient provides energy for uptake of sodium ions against the electrochemical gradient. A substance that blocks sodium ions from binding to the cotransport protein will also block the transport of glucose. The cotransporter can also transport potassium ions. Sodium and glucose compete for the same binding site in the cotransporter.

Answer 1

The correct answer is: A substance that blocks sodium ions from binding to the cotransport protein will also block the transport of glucose.

The Sodium Glucose Linked Transporters (SGLT) require the energy to transport glucose (uphill glucose gradient). They use that energy from this downhill sodium ion gradient created by the ATPase pump.  

Answer 2

The answer is A substance that blocks sodium ions from binding to the cotransport protein will also block the transport of glucose.

Sodium ions are necessary for regulation of blood and body fluids, transmission of nerve impulses, heart activity, and certain metabolic functions. Physiologically, it exists as an ion in the body. Sodium is needed by animals, which maintain high concentrations in their blood and extracellular fluids, but the ion is not needed by plants.