Question

What metabolic pathway forms the following conversion OH I-O C=0 C=0 H-C-OH C=0 HO-C-H 2 4 H-CH H-C-OH H-C-OH H 1 CH2OH (A) Glycolysis (B) Kreb's Cycle (C) Chemiosmosis (D) Fermentation a.(a) Ob.(b) OC(C) d.(d) Moving to another question will save this response

Answer 1

It is (a) Glycolysis.The first molecule is Gluecose and the second molecule is Pyruvic acid. In glycolysis gluecose is converted into 2 molecules of pyruvic acid, releasing energy.

The whole reaction is

$Fructose-6-Phosphate + ATP+ iP--> Fructose-1,6-biphosphate--> Glyceraldehyde-3-phosphate\leftrightharpoons Diydroxy acetone phosphate (triosephosphate)$

In aerobic organisms glycolysisis the only process in respiration. In this gluecose undergoes partial oxidation to form two molecules of pyruvic acid. In plants this gluecose is derived from sucrose that is the end process of photosynthesis or from storage carbohydrates.

Sucrose is converted into gluecose and fructose by enzyme invertase and these two monosaccharides enter the glycolytic pathway.

Gluecose and fructose are phosphorylated to gove gluecose-6-phosphateby enzyme hexokinase. This then isomerises to produced fructose-6-phosphate. A chain of 10 reactions under control of different enzymes happen to produce pyruvate from gluecose.

ATP is ultilised in two steps in conversion of gluecose to gluecose-6-phosphate and second in conversion of fructose to fructose-1,6-biphosphate. This is split in dihyroxyacetone phosphate and 3-phosphoglycealdehyde. NADH is formed when 3 phosphoglycerate is converted into 1,3-biphosphoglycerate.

Coversion of BPGA into to 3-phosphoglyecric acid also yield energy in form of ATP. During conversion of PEP into pyruvic acid also yield ATP. Pyruvic acid is the key product of glycolysis.