Question

Define and briefly explain about glycolysis kreb cycle and gluconesenesis

Answer 1

Glycolysis and Gluconeogenesis: Glycolysis/Gluconeogenesis is the set of reactions that converts glucose into pyruvate. Glycolysis is a compilation of ten reactions (with 1 being an isomerization of 2 products into one another) of glycolysis take place in the cytoplasm

Glycolysis is the break down of glucose to give a net yield of two molecules of pyruvate, two ATPS and two NADH + H+. ... In the presence of oxygen, pyruvate is oxidized and acetyl CoA is formed, which feeds into the citrate acid cycle and the complete oxidation of glucose.

Answer 2

➡️Glycolysis is a metabolic process that breaks down carbohydrates and sugars ( glucose) into lactic acid or pyruvic acid and releases energy.✔️

➡️Krebs cycle is a series of enzymatic reactions that takes place in mitochondria.✔️


➡️1. The first step in glycolysis is conversion of Glucose→Glucose 6-phosphate and the enzyme which catalyzes this reaction is hexokinase. Kinases are the enzymes which are involved in transfer phosphate group, and the enzyme hexokinase transfers phosphate group to the 6th carbon in glucose, hexokinase requires ATP (ATP→ ADP) and magnesium ion to catalyze this reaction the name of this particular enzyme is hexokinase because it phosphorylates glucose which is a 6 carbon compound and hexo signifies 6 carbon compond.✔️

➡️2. The second step in glycolysis is the conversion of Glucose 6-phosphate→Fructose 6-phosphate. Since this process requires isomerization from an aldose (aldehyde) to ketose (ketone), the enzyme used is phosphohexose isomerase.✔️

➡️3. The third step in glycolysis is Fructose 6-phosphate→Fructose 1,6-bisphosphate, this reaction also needs phosphorylation and hence it is catalyzed by a kinase which transfers the phosphate group from ATP to the compound. Another molecule of ATP is used and converted to ADP in this reaction. The enzyme is phosphofructokinase. ✔️

➡️4. Fructose 1,6-bisphosphate is cleaved to give two 3 carbon compounds which are glyceraldehyde 3- phosphate and dihyroxyacetone phosphate. The enzyme used is aldolase.✔️

➡️5. Glyceraldehyde 3-phosphate and dihydroxyacetone phosphate are isomers and can be interconverted by the enzyme triose phosphate isomerase.✔️

➡️6. Glyceraldehyde 3-phosphate→1,3-Bisphosphoglycerate, the enzyme used is glyceraldehyde 3-phosphate dehydrogenase which uses NAD+ which gets converted to NADH.✔️

➡️7. The next reaction is 1,3-Bisphosphoglycerate→3-phosphoglycerate, one phosphate group is lost to ADP to generate ATP, the enzyme used isphosphoglycerate kinase.✔️

➡️8. 3-phosphoglycerate→2-phosphoglycerate, the position of phosphate group is shifted by enzyme phosphoglycerate mutase.✔️

➡️9. 2-phosphoglycerate→phosphoenolpyruvate, this reaction involves dehydration (removal of water molecule) and the enzyme is enolase.✔️

10. phosphoenolpyruvate→pyruvate, the phosphate group is lost to ADP and ATP is formed, the enzyme catalyzing this reaction is pyruvate kinase.