Biology CLEP Prep Practice Exam

What is the chemiosmotic theory?

1. A theory describing the passive movement of molecules.

2. A theory explaining the production of ATP by the mitochondria.

3. A theory concerning the origin of life.

4. A theory describing the movement of molecules through active transport.

The correct answer is: A theory explaining the production of ATP by the mitochondria.

The chemiosmotic theory explains how ATP, the main source of energy for cells, is produced in the mitochondria through a process called oxidative phosphorylation. This theory states that the production of ATP is driven by the movement of protons (H+) across a concentration gradient, which is created by the electron transport chain embedded in the mitochondria's inner membrane. Option A is incorrect because it is a broad statement about the movement of molecules, while the chemiosmotic theory specifically focuses on the production of ATP in the mitochondria. Option C is incorrect because it is a theory about the origin of life, which is unrelated to the function of ATP in cells. Option D is incorrect because it refers to active transport, which is a different process than the passive transport of protons described in the chemiosmotic theory.