Osmosis describes the movement of water across a biological membrane and down its concentration gradient. In chemiosmosis, useful energy is harnessed by the cell from the movement of across the inner mitochondrial membrane into the matrix a concentration gradient.

A)ATP, against
B)protons, down
C)electrons, down
D)ADP, against

B)protons, down

Explanation:

Chemiosmosis is the diffusion of ions through a selective permeable membrane. It specifically refers to the production of ATP through the movement of hydrogen ions through an inner membrane during cellular respiration. Hydrogen ions diffuse from an area of high proton concentration to one of lower concentration.

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.