Alkaliphiles maintain an inverted pH gradient in which:
A) the pH in their immediate environment is lower than the cytoplasmic pH
B) their immediate environment has a pH several units above that of the cytoplasm
C) pH in the immediate environment is equal to that of the cytoplasm
D) all of the above
E) none of the above

Question

Quizplus · Accepted Answer

Alkaliphiles maintain an inverted pH gradient, meaning that the pH in their immediate environment is several units above that of their cytoplasm. This is achieved through various mechanisms, such as pumping protons out of the cytoplasm, synthesizing and expelling ammonia, and buffering with bicarbonate ions. Option A is incorrect because the pH in their immediate environment is higher, not lower, than the cytoplasmic pH. Option C is incorrect because an inverted pH gradient requires a significant pH difference between the cytoplasm and immediate environment. Option D is incorrect because options A and C are incorrect. Therefore, the correct answer is B.

Alkaliphiles Maintain an Inverted PH Gradient in Which