Which characteristic best distinguishes glycolysis and the krebs cycle from the electron transport chain? a. the amount of atp produced b. the location in which they occur c. whether glucose is broken down d. whether they occur in plants or animals

The characteristic best distinguishes glycolysis and the Krebs cycle from the electron transport chain is  the amount of ATP produced . In glycolysis net ATp production is 2 ATP and in 1 Kreb's cycle 38 ATP are produced. Hence option A is correct.

A. the amount of ATP produced

Explanation:

Glycolysis and Krebs cycle form total 4 ATPs (2 ATP from each pathway) while the electron transport chain present in inner mitochondrial membrane produces as many as 32-34 ATPs by oxidative phosphorylation.

The reducing powers NADH and FADH2 formed during glycolysis and Krebs cycle enter the electron transport chain and donate their electrons to molecular oxygen.

Transport of electrons from these reducing powers to molecular oxygen via electron transport chain generates the proton motive force which in turn drives the synthesis of a large number of ATPs.