AP BIOLOGY

Detailed explanation-1: -In mitochondria, chemiosmosis translocates protons from the matrix into the intermembrane space, whereas in chloroplasts, chemiosmosis translocates protons from. the stroma to the photosystem II.

Detailed explanation-2: -One of the major differences between chemiosmosis in mitochondria and in chloroplasts is the source of energy. In mitochondria, the high-energy electrons are extracted from the food molecule (from redox reaction) whereas in chloroplast the source is from the photons captured from the light source.

Detailed explanation-3: -Chemiosmosis involves the pumping of protons through special channels in the membranes of mitochondria from the inner to the outer compartment. The pumping establishes a proton (H+) gradient. After the gradient is established, protons diffuse down the gradient through a transport protein called ATP synthase.

Detailed explanation-4: -Chemiosmosis refers to the process of moving ions to the other side of a biological membrane. An electrochemical gradient is generated in chemiosmosis. It is used to drive ATP synthesis. During this process, hydrogen ions accumulate in the thylakoid membranes.

Detailed explanation-5: -In chloroplasts, for example, an electron transport chain transfers ions (protons) from the stroma (fluid) through the thylakoid membrane to the thylakoid gaps during photosynthesis. Chemiosmosis occurs mainly in the thylakoids of chloroplast.