Aquaporins
a. are found in all cells.
b. allow water to cross the plasma membrane against its concentration gradient.
c. allow for the active transport of water.
d. allow water to cross the plasma membrane via facilitated diffusion

Aquaporins allow for the active transport of water.

Aquaporins (AQP) are protein membrane that serve as channels for the transportation of water and sometimes small solutes across the membrane. They are usually found in bacteria, plants, and animals.

The main function of Aquaporins is the transportation of water between cells.

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d. allow water to cross the plasma membrane via facilitated diffusion

Explanation:yeah

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.