Question

Which of the following statements is true?

A. Glycolysis occurs in the intermembrane space of the mitochondria

B. Molecules of NAD+ acquire electrons during glycolysis

C. ATP, FADH2, and O2 are produced during glycolysis

D. The rate of glycolysis increases in response to low concentrations of ADP

E. None of the above

Answer 1

B. Molecules of NAD+ acquire electrons during glycolysis

Some molecules like NAD+ and FAD act as electron carriers during cellular respiration. The NAD+ molecules accept two electrons and one hydrogen H+ and become reduced in chemical reactions like glycolysis and Krebs cycle. During ETS, NADH donates these pairs of electrons and becomes oxidized.

During glycolysis ATP and NADH are formed, and it is the first step that occurs in the cell's cytoplasm. Phosphofructokinase enzyme is the main control element in the glycolytic pathway. ATP is the negative regulator of PFK and AMP is the negative regulator. This means if ATP is high, glycolysis is no more needed to produce ATP while if AMP levels are high, the cell is starved for energy, and glycolysis occurs quickly to replenish ATP.