The different proteins found within eukaryotic cell membranes affect the function of the membranes. Which of the followin functions is most likelv provided by channel and carrier proteins that are embedded within the cell membranes?

a- They allow the cell membrane to produce energy.
b- They allow specific substances to enter the cell.
c- They provide protection for the cell membrane.
d- They aid in the digestion of foreign invaders.

b- They allow specific substances to enter the cell.