MICROANATOMY

Detailed explanation-1: -Fermentation happens in anaerobic conditions (i.e., without oxygen). Fermentation begins with glycolysis which breaks down glucose into two pyruvate molecules and produces two ATP (net) and two NADH. Fermentation allows glucose to be continuously broken down to make ATP due to the recycling of NADH to NAD+.

Detailed explanation-2: -Glycolysis occurs in both aerobic and anaerobic states.

Detailed explanation-3: -Anaerobic bacteria ferment carbohydrates and amino acids to obtain energy for growth. Due to the absence of oxygen and other inorganic electron acceptors, the substrate of a fermentation has to serve as electron donor as well as acceptor, which results in low free energies as compared to that of aerobic oxidations.