Question

a sodium ion moves into a cell while a potassium ion moves out of the cell using the same channel. the type of directional transport is called. active transport. passive transport. antiport. symport.

Explanation:

Antiport is a type of cotransport where two different substances move in opposite directions across a cell membrane through the same channel or carrier protein. This matches the description of sodium moving into the cell and potassium moving out via the same channel. Active/passive transport refer to energy use, not directional movement of two solutes, while symport involves movement in the same direction.

Answer:

Antiport.