Question

What occurs in glycolysis?
A) Fixation
B) Reduction
C) Dehydrogenation
D) Oxidation

Answer 1

Hint:Glycolysis is defined as a metabolic pathway responsible for the conversion of glucose molecules into pyruvate.

Complete answer:
Glycolysis occurs both in aerobic and anaerobic organisms and is considered as the first pathway executing glucose metabolism. The glycolytic reaction sequence differs between species due to its regulation mechanism and the subsequent metabolic fate of its end product. The aerobic organisms show glycolysis as a precluding event to the Citric Acid Cycle and the Electron Transport Chain which together is responsible for the energy release that is contained in the glucose molecule.
Option A: Biological fixation process refers to the process of trapping and converting free atmospheric nitrogen to nitrogenous compounds which are later stored within the plant tissues. This process is found in Rhizobacteria, Azotobacter, and Agrobacterium. Therefore, this is the incorrect option.
Option B: Reduction reaction is defined as a process wherein a species gains electrons thereby reducing its oxidation state. Therefore, this is the incorrect option.
Option C: Dehydrogenation reaction involves removal of hydrogen atom from an organic molecule. This process is considered to be the reverse of hydrogenation. Therefore, this is the incorrect option.
Option D: Oxidation is defined as the process of being oxidised by the loss of electrons. Thus, this is the correct option as the process of glycolysis involves glucose oxidation. Whatever free energy is released into the atmosphere in this entire process, it gets used up for the formation of high-energy compounds such as NADH and ATP. Therefore, this is the correct option.

Thus, the correct option is (D)oxidation.

Note:The overall glycolysis process involves oxidation of glucose to pyruvate, reduction of NAD+ to NADH, and phosphorylation of the ADP to ATP.