Final answer:
The proton motive force consists of two components: a pH gradient and an electric potential difference across a membrane, which are established by movement of protons via the electron transport chain and used for ATP synthesis during oxidative phosphorylation.
Step-by-step explanation:
The two components that make up the proton motive force (PMF) are the difference in proton concentration (also known as a pH gradient) and a difference in electric potential across a membrane. Essentially, it is an electrochemical gradient. The movement of electrons down the electron transport chain helps to pump protons across the membrane, leading to an accumulation of hydrogen ions (H+) on one side, making that side more acidic. This accumulated potential energy is stored and can then be used for making ATP during oxidative phosphorylation by allowing the protons to flow back through ATP synthase.
This process is not only essential for ATP synthesis, but it also powers other cellular functions such as nutrient transport and flagella rotation for motility. The PMF, therefore, plays a pivotal role in the cell's energy conversion processes and overall metabolism.