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

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

d. planting trees

the trees take in carbon to make oxygen.