Question

Which of the following correctly characterizes the F1 subunit of ATP synthase?

a. It is embedded in the inner mitochondrial membrane.

b. It forms the channel through which protons flow.

c. It is the catalytic unit that synthesizes ATP.

d. None of these answer options correctly characterizes the F1 subunit of ATP synthase.

Answer 1

The F1 subunit of ATP synthase is the catalytic unit that synthesizes ATP, converting ADP and inorganic phosphate into ATP via oxidative phosphorylation, and is not embedded in the inner mitochondrial membrane.

Step-by-step explanation:

The F1 subunit of ATP synthase correctly characterizes option c: It is the catalytic unit that synthesizes ATP. The F1 portion is not embedded in the inner mitochondrial membrane; this is the role of the Fo portion, which forms the channel through which protons flow and is involved in the rotation that drives the ATP synthesis. The F1 subunit protrudes into the mitochondrial matrix and uses the energy derived from the rotation of the Fo portion to catalyze the conversion of ADP and inorganic phosphate (Pi) into ATP, a process known as oxidative phosphorylation. Hence, the F1 subunit's primary role is enzymatic, facilitating the production of ATP from its substrates.