What is number of ATP molecules produced per molecule of glucose when Pyruvate is used to produce NADH, ATP, and FADH2

2 ATP molecules.

Explanation:

This question is describing KREB'S CYCLE, which is the second stage of aerobic cellular respiration that occurs in the mitochondrion. In the Kreb's cycle, also known as tricarboxylic acid cycle, pyruvic acid (product of glycolysis) is oxidized to produce NADH, FADH2, ATP and CO2 as products.

In a nutshell, per glucose molecule that begins the respiration process (glycolysis), 2 molecules of ATP are produced alongside 3 NADH and 1 FADH2 molecules in the Krebs cycle. Note that, the electron carriers (NADH and FADH2) are used in the electron transport chain.