Question

Decide whether the following statement is TRUE or FALSE.

A symporter would function as an antiporter if its orientation in the membrane were reversed (that is, if the portion of the protein normally exposed to the cytosol faced the outside of the cell instead).

Answer 1

False

Explanation:

Uniporters, symporters, and antiporters are membrane proteins that transport​ substances across cell membranes. Uniporters are proteins that carry one specific ion or molecule. Moreover, symporters are carriers that transport at least two substrates/solutes in the same direction, i.e., from one side of the membrane to the other at the same time. On the other hand, antiporters are carrier proteins that catalyze the exchange of two substrates/solutes (ions or molecules) in opposite directions at the same time. In consequence, turning around a symporter would not convert it into an antiporter, only would cause the symporter to bind two solutes on the opposite side of the membrane.