Question 3
The fluid-mosaic model of the cell membrane suggests that the membrane is primarily composed of proteins and lipids. Which of the following is a function of proteins in the cell membrane?
Α
to allow substances to cross the plasma membrane via active transport
B
to provide a hydrophilic head so that water can enter the cell
С
to package and sort molecules to be sent in vesicles
D
to read messenger RNA to assemble amino acids