NEET Practice Questions (MCQs) with Answers & Solutions

The respiratory quotient (R.Q.) of anaerobic respiration is infinity. This is because in anaerobic respiration, no oxygen is consumed while carbon dioxide may still be produced, leading to an undefined or infinite R.Q. value.

When the amount of CO₂ taken from the atmosphere during photosynthesis equals the amount of CO₂ released into the atmosphere during respiration, it is called the 'compensation point'. At this point, there is no net gain or loss of CO₂ in the environment.

Glycolysis is the metabolic pathway that occurs in the cytoplasm of cells and is common to both aerobic and anaerobic respiration. It breaks down one molecule of glucose into two molecules of pyruvate, yielding 2 ATP molecules in the process. The Krebs cycle and Electron Transport System (ETS) are specific to aerobic respiration.

During glycolysis, a total of 4 ATP molecules are produced through substrate-level phosphorylation. Although 2 ATP molecules are consumed in the earlier steps, the net gain is 2 ATP. However, the question specifically asks about the number of ATP formed during dephosphorylation, which refers to the actual production phase, thus 4 ATP are formed.

The enzyme required to convert pyruvic acid to acetaldehyde is Pyruvic acid decarboxylase. This enzyme catalyzes the decarboxylation of pyruvic acid to acetaldehyde and carbon dioxide.

Phosphorylation generally refers to the addition of a phosphate group (PO4) to a molecule. This could involve combining phosphoric acid with a chemical compound. It is a crucial process in various metabolic pathways.

During glycolysis, fructose 1,6-bisphosphate is split by the enzyme aldolase into two three-carbon molecules: glyceraldehyde 3-phosphate (PGAL) and dihydroxyacetone phosphate (DHAP).

Oxidative phosphorylation occurs in the cristae of the mitochondria. The electron transport chain and ATP synthase are located on the inner mitochondrial membrane, which is folded into cristae to increase the surface area for this process.

Malic acid is formed from fumaric acid by the addition of a water molecule (H2O). This hydration reaction is catalyzed by the enzyme fumarase in the citric acid cycle (Krebs cycle).