Question

Summarize the process of photosynthesis, including the Calvin cycle, being sure to explain which compounds undergo reduction and which undergo oxidation.

Answer 1

The photosynthesis is an important process which is followed by plants, algae, and blue-green bacteria in which they trap sunlight and convert it into chemical energy. The trap the sunlight through the chlorophyll which is a green pigment and through series of process help in converting it into chemical energy. The light energy is captured, and it is used to convert water and CO2 into oxygen and molecules which can provide energy.

The main purpose of the Calvin cycle is that through a series of biochemical reactions, it enables the plants and other photosynthetic organisms to produce sugar which is an energy molecule from sunlight and carbon source. It is light independent redox reactions where it fixes the CO2 and convert it into sugar molecule. These reactions occur within the stroma of the chloroplast and this cycle takes place in two parts. The first stage of the Calvin cycle is the light reaction where it uses the light energy and produces ATP and NADPH. The second stage of the Calvin cycle is the one in which it is dark ratio and the CO2 and water is converted into organic sugar molecule like glucose which helps in producing energy. The first process in which CO2 is fixed and forms sugar is dependent on ATP and NADPH.

· The first step is called carbon fixation and in which the CO2 combines with ribulose-1,5-bisphosphate. In this it helps in splitting the CO2 molecule into three molecule compound of 3-phosphoglyceric acic.

· In the reduction stage, it uses ATP and NADPH are reduced and it helps in converting te 3-PGA into glyceraldehyde. In this NADPH is reduced after donating electron.

· After this glyceraldehyde makes glucose and some of them recycles and generates RuBP acceptor. In this process ATP is required.