Question

Reaction C GOLD Water Water Reaction G

1) What is the letters A-H represent?
2) What type of evolution (convergent, coevolution, gradualism, disruptive selection or stabilizing selection) was responsible for creating the symbiotic relationship between B & F?
3) What reaction(Glycolysis, Krebs Cycle, ETC) does letter D enter?
4) Do all reactions (Glycolysis, Oxidation of pyruvate, Krebs Cycle, ETC) create chemical H?

Answer 1

1) The letter A-H represent the following things which are discussed below

Letter A represent sunlight which is the source of photons for all the autotrophic plants. Plant uses sunlight as a source of light energy and convert it into chemical energy through the process discussed by letter B .

Letter B represent the chloroplast where sunlight is trapped through the grana (stack of thylakoid) and  the light energy of sunlight gets converted into chemical energy by oxidation of water. Oxidation of water release oxygen and also provide electron and proton for the formation of NADPH and ATP respectively which is used for the reduction of carbon dioxide through C3 cycle which takes place in chloroplast matrix called stroma so  that it can be used in biological system for the metabolism.

Letter C represent the dark reaction where carboxylation and reduction of carbon dioxide occurs and also regeneration of ribulose bisphosphate occurs. This reaction through reduction of carbon dioxide produce triose (simple sugar) containing three carbon. One sixth of the produced triose get exported to cytosol for sucrose synthesis or get converted into chloroplast inside the chloroplast.

Letter D represent the glycolysis in which sucrose or glucose is converted into pyruvate and during this series of chemical reaction high energy molecule (ATP) is formed which is one of the energy currency of biological system.

Letter E represent the energy produced after Kreb's cycle and ETC (electron transport chain) that is ATP.

Letter F represent mitochondria (the power house of cell) where Kreb's cycle and ETC takes place in mitoplast and mitochondrial membrane respectively.

Letter G represent the Kreb's cycle which occurs in mitochondrial matrix and produce carbon dioxide.

Letter H is the chemical which is produced after Kreb's cycle and oxidation of pyruvate during link reaction. This chemical is known as carbon dioxide which act as a source of carbon for the dark reaction.

2) The type of evolution which is responsible for creation symbiosis between B and F is convergent evolution as this evolution state that a type of selection in which two or more organisms evolve independently but show similar trait as a result of same environment or ecological niche. Mitochondria and chloroplast are assumed to be organism evolved differently but evolve the same character of endosymbiosis.

Co- evolution is evolutionary theory in which two or more organism evolve in a tandem manner by exerting selection pressure on each other which does not occurs in  the case of chloroplast and mitochondria.

Gradualism is theory which explain how single organism evolve by accumulation of variation in pre-existing species in gradual fashion.

Disruptive selection is the type of natural selection in which variation produces two different types of character in single organism which is selected over intermediate character. This doesn't occur in B and F as they both are different organism evolved differently.

Stabilizing selection favors intermediate trait over two extreme trait This doesn't occur in B and F as they both are different organism evolved differently..

so all the four type of evolution other than convergent evolution does not explain the symbiotic relationship between mitochondria and chloroplast.

3) The D enters the Kreb's cycle as glycolysis and ETC doesn't produce carbon dioxide (H) which is the result of reaction D

4) No all reaction doesn't create chemical H, only Kreb's cycle and pyruvate oxidation produce carbon dioxide where as glycolysis and ETC does not produce carbon dioxide.