12. Microbial Metabolism

Where does the first stage of aerobic cellular respiration take place within a cell?

a) Mitochondrial matrix.

b) Inner mitochondrial membrane.

c) Intermembrane space.

d) Cytoplasm.

Starting with one molecule of glucose, glycolysis results in the net production of which of the following sets of energy-containing products?

a) 2 NAD⁺, 2 pyruvate, and 2 ATP.

b) 2 NADH, 2 pyruvate, and 2 ATP.

c) 4 NADH, 2 pyruvate, and 4 ATP.

d) 6 CO₂, 2 pyruvate, and 2 ATP.

Which of the following is a result of glycolysis?

a) A net gain of four ATP per one glucose molecule.

b) Conversion of FAD to FADH₂.

c) Conversion of one glucose molecule to two pyruvate molecules.

d) Conversion of NADH to NAD⁺.

The glycolysis pathway is basically _______.

a. catabolic

b. amphibolic

c. anabolic

d. cyclical

Two ATP molecules are used to initiate glycolysis. Enzymes generate molecules of ATP for each molecule of glucose that undergoes glycolysis. Thus, a net gain of _________ molecules of ATP is produced in glycolysis.

The initial catabolism of glucose occurs by glycolysis and/or the ________ and ________pathways.

Explain the mechanism of negative feedback with respect to enzyme action.