Question

What is the most common transport mechanism by which glucose and other organic solutes cross the luminal membrane of an epithelial cell layer?

Answer 1

Secondary active cotransport with Na+

Step-by-step explanation:

Secondary active transport is a form of active transport across a biological membrane by which the transport protein couples the movement of an ion (typically Na+ or H+) down its electrochemical gradient to the uphill movement of another molecule or ion (here being glucose) against a concentration/electrochemical gradient.

Answer 2

Secondary active co-transport with Na+.

Step-by-step explanation:

Secondary active transport is most common transport method, and it is defined as the transport of molecules against the electrochemical gradient across a membrane from the region of lower concentration to the region of higher concentration. Secondary active transport is two types:

1) Co-transport (symport)

2) Exchange (antiport)

In co-transport, the direction of transport of driving ion, and driven molecule is same, such as Na+/glucose co-transport is present in the kidney proximal tubules, and small intestine, at the same time transports one glucose molecule, and two Na+ ions into the cell across the plasma membrane.