Cell membrane

Question 1

cell membrane

Answer 1

(also known as plasma membrane) separates internal metabolic events from the external environment. This layer is semi-permeable – only small, uncharged, polar molecules can pass through (H20 and C02).

Question 2

channel proteins

Answer 2

provide passageways through the membrane for water-soluble substances.

Question 3

transport proteins

Answer 3

spend energy (ATP) to transfer materials across the membrane.

Question 4

Receptor proteins

Answer 4

initiate specific cell responses once hormones or other trigger molecules bind to them.

Question 5

electron transfer proteins

Answer 5

move electrons from one molecule to another.