Answer:
(a) an aquaporin
Explanation:
An aquaporin is a water channel which forms a pore in the cell membrane and facilitates the movement of water. Aquaporin is an integral membrane protein (permanently attached to the membrane) that enables the in and out flow of the water. This channel also prevents the passage of ions and other solutes, so it cannot change the voltage. There are four types of aquaporins, and they are mostly found in the kidney with the function of water reabsorption.
Answer:
Cardiovascular system
Explanation:
Cardiovascular means relating to the heart and blood vessels. Even though blood system sounds like an appropriate name, the circulatory system studies more than just blood, it studies the heat and blood vessels as well.
A I believe, hope it helps.
