Botany MCQs for NEET — Practice Questions with Answers

In the Electron Transport System (ETS), one molecule of FADH2 contributes to the production of approximately 2 ATP molecules. FADH2 enters the ETS at Complex II, bypassing Complex I, leading to the generation of fewer ATP compared to NADH.

The formation of ATP occurs on the F₁F₀ particles, also known as ATP synthase, which is located in the inner mitochondrial membrane. ATP synthase uses the proton gradient generated by the electron transport chain to synthesize ATP from ADP and inorganic phosphate.

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).