The electron transport chain consists of protein complexes embedded in the inner mitochondrial membrane, where it generates a proton gradient by a series of oxidation‑reduction, or redox, reactions. Although all of the stages of cellular respiration (glycolysis, the citric acid cycle, and the electron transport chain) are necessary for life, the electron transport chain is sometimes called the most important stage. First complete the sentence, then answer the question.

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It is potential energy that can power ATP synthesis

Explanation:

Electron transport chain is considered the most important stage of the cellular respiration as it is the only stage during which a high amount of ATP is produced.

The electron transport through various protein complex where electrons lose its energy and are used to drive the outflow of the proton to the outside of the mitochondrial membrane.

When protons accumulate outside the membrane creates a proton gradient as a result of which the proton needs to enter the cell. The protons enter through the ATP synthase where the potential energy of the proton is used to rotate the rotor and thus ATP is formed from the ADP.

Thus, the selected option is correct.

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.