Question

1. During which stage of the calvin cycle is PGA produced?

2. in the transport chain, cytochrome c oxidase obtains electrons from

3. in the electron transport chain nadh donates its electron to ____________.

Answer 1

1. Calvin cycle is light dependent reaction in photosynthesis. It helps in the fixation of carbon dioxide. Calvin cycle has 3 stages. The first stage of Calvin cycle is enzyme RUBISCO reacts with CO2 to form 6 molecules of 3- phospho glyceric acid (PGA). Thus, the carbon dioxide fixation is called 1st stage in which PGA is produced. Reduction of PGA and regeneration of RUBP are next two stages.

2. In electron transport chain Cytochrome C oxidase is the last enzyme that receives electrons from Cytochrome C molecules and helps in converting Oxygen to water molecules.

3. There are four enzyme complexes in the mitochondrial membrane helps in the electron transport chain. Among them first complex is the NADH dehydrogenase which is called Complex-I. This complex receives electrons from the donor molecule called NADH. Hence, the answer is complex-l or NADH dehydrogenase.