Question

What is produced when succinyl CoA is changed to succinate?
A. ATP
B. GTP
C. CTP
D. ATP in plants and GTP in animals.

Answer 1

Hint: Aerobic respiration is the breakdown of nutrients from food to simpler products such as carbon dioxide, water and produces energy. The process of respiration produces energy which the living organism requires to drive various biological processes.

Complete answer:
The aerobic respiration is important for oxidation of the sugars present in the food into simpler components which can be readily utilized by the cells. It leads to the formation of energy which is required for carrying out different life processes. The process starts with the oxidation of glucose and formation of pyruvic acid which takes place in cycle and the process is known as oxidative decarboxylation. It converts the pyruvate into acetyl coenzyme A and two molecules of carbon dioxide. The pyruvic acid formed then enters the next stage of the cycle which is the Krebs cycle or the Calvin cycle.
In the Krebs cycle, the pyruvates formed in the glycolysis is completely broken down into water, carbon dioxide and generates ATP through oxidative phosphorylation. The Kreb cycle is also known as the citric acid cycle and takes place in the mitochondria. The process produces a series of intermediate compounds and produces energy through substrate phosphorylation.
The citric acid cycle comprises eight distinct steps. IT begins when acetyl CoA is transferred to oxaloacetate. The oxaloacetate is converted into citrate. The citrate is then rearranged to form isocitric acid. The six carbon isocitric acid is oxidized into five carbon alpha ketoglutaric acid. It is then converted into succinyl CoA by removal of carbon dioxide and addition of CoA. The next step involves the conversion of succinyl CoA into succinic acid. During this process, the CoA is removed and the energy released is used for the formation of GTP molecules. In animal cells, GTP is produced through this process which can be further used to form ATP. In plants, this step produces ATP. Succinyl CoA is actively involved in the synthesis of chlorophyll in plants and also forms cytochromes and phytochromes.

Therefore, the correct option is option D.

Note:
The process of Kreb Cycle is completed in several different steps. The conversion of succinyl CoA into succinic acid involves the removal of the CoA enzyme and the step produces energy in the form of GTP. This step produces ATP in plants.