cell membrane

Question 1

lipid bilayer

Answer 1

(fluid mosaic diagram.) The exposed head is hydrophilic and the internal layer is hydrophobic.

Question 2

channel proteins

Answer 2

found in the membrane are used for active transport or facilitated diffusion of substances eg. Insulin.
it depends on the concentration gradient and concentration outside the cell that determines which use

Question 3

carrier proteins

Answer 3

found in membrane are used for facilitated diffusion. It transports the molecule in and out of the cell

Question 4

pump protein

Answer 4

pump something (usually ions) from areas of low concentration to higher concentration