Question

What is co-transport?

Answer 1

Cotransport is the process in which two substrates are simultaneously transported across a membrane by one protein/protein complex which does not have ATPase activity.

Explanation:

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Cotransport is brought about by a subcategory of membrane transport proteins called as cotransporters. The movement occurs by binding to two molecules or ions at a time and using the gradient of one solute's concentration to force the other molecule or ion against its gradient. These proteins undergo a cycle of conformational changes by linking the movement of an ion with its concentration gradient to the movement of a cotransported solute against its concentration gradient.

When both substances are transported in the same direction the transport protein is known as symport. When the substances are transported in the opposite direction the transport protein is known as an antiport.