Question

Organisms that live at low pH (acidophiles) have to maintain a homeostasis of a pH-neutral cytoplasm by moving protons from the inside of the cell to the outside of the cell, where there is already a high concentration of protons. Which of the following types of transport are these acidophilic organisms likely to use?
active transport
facilitated diffusion
simple diffusion
osmosis

Answer 1

acidophilic organisms are likely to use active transport to move protons from the inside of the cell to the outside of the cell. Active transport requires the cell to expend energy to move molecules or ions against their concentration gradient, which is necessary in this case to maintain homeostasis of a pH-neutral cytoplasm in a low pH environment. Facilitated diffusion, simple diffusion, and osmosis do not require energy expenditure and would not be effective in this scenario.