question_answer 45)

  RuBP carboxylase, PEPcase, pyruvate dehydrogenase, ATPase, cytochrome oxidase, hexokinase, lactate dehydrogenase. Select/choose enzymes from the list above which are involved in (a) Photosynthesis                (b) Respiration (c) Both in photosynthesis and respiration    

Answer:

                RuBP Carboxylase This is a part of dark reaction of photosynthesis. It catalyses the fixing of in  cycle. PEPcase This is a part of photosynthesis of plants. It catalyses the reaction of fixing of  to form first stable product oxaloacetate. 4 carbon compound. Pyruvate dehydrogenase It is involved in aerobic respiration and catalyses the reaction of formation of acetyl Co-A from pyruvic acid. It requires the participation of NAD and Co-enzyme-A.                                            Pyruvicacid ATPase It is a part of both respiration and photosynthesis. Both these processes uses electron transport chain and associated proton pump and ATP synthase as a key part of process. ETC uses the energy to pump hydrogen ions across a membrane. The protons flows back through ATP synthase, driving the production of ATP. Cytochrome Oxidase This is involved in both respiration and photosynthesis. It is an electron carrier in the electron transport chain. Hexokinase This enzyme is also involved in, respiration. In glycolysis, it catalyses the first reaction, i.e., formation of glucose -6- phosphate from glucose molecule. It uses one ATP molecule which transfers  group to glucose molecules. The first step of glycolysis Lactate Dehydrogenase This enzyme is involved in anaerobic respiration in bacteria Lactobacillus. Pyruvic acid formed at the end of glycolysis is converted to lactic acid by homo-fermentative lactic acid bacteria. Hydrogen from NADH molecule is transferred to pyruvate is transferred to pyruvate molecule lactic acid molecule leading formation of acid.