AP BIOLOGY

Detailed explanation-1: -In the process of fermentation the NADH + H+ from glycolysis will be recycled back to NAD+ so that glycolysis can continue. In the process of glycolysis, NAD+ is reduced to form NADH + H+. If NAD+ is not present, glycolysis will not be able to continue.

Detailed explanation-2: -The NADH (biological substance producing energy) gets recycled by the fermentation process into NAD+ to allow glycolysis to generate ATP without oxygen.

Detailed explanation-3: -The process of fermentation results in the reduction of pyruvate to form lactic acid and the oxidation of NADH to form NAD+.

Detailed explanation-4: -Lactic Acid Fermentation Most organisms carry out fermentation through a chemical reaction that converts the pyruvate from glycolysis into lactic acid or lactate. Lactic acid fermentation also converts NADH into NAD+ so that glycolysis can continue. The following diagram shows a summary of lactic acid fermentation.

Detailed explanation-5: -During NADH regeneration, the two pyruvate molecules are first converted to two acetaldehyde molecules, releasing two carbon dioxide molecules in the process. The two NADH then donate electrons and hydrogen atoms to the two acetaldehyde molecules, producing two ethanol molecules and regenerating NAD+.