Question

A protein channel, like the peripheral and integral proteins in the diagram, is a transport protein that. A.always moves substances against a concentration gradient. B.always moves substances with a concentration gradient. C.serves as a tunnel for specific substances. D.always requires energy from the cell. i'm thinking A or D but i'm not sure.

Answer 1

A protein channel, like the peripheral and integral proteins in the diagram, is a transport protein that : C. Serves as a tunnel for specific substances

Protein channel serves as tunnel across the membrane to the cell for a specific substance such as CACLCIUM

hope this helps