Answer: a. oxygen
Basically what (/the) ETC and oxidative phosphorylation is, is the products of the Krebs cycle being oxidized and oxygen receiving electrons. And when the phosphorylation part of oxidative phosphorylation occurs is when ADP gains its third phosphate group becoming ATP.
Forgive me for this poor response I was trying to be quick and it resulted in this vague and disorganized mess. To properly explain the ETC and oxidative phosphorylation it would be best to start from the beginning and explain all the stages of Aerobic respiration. Then it would be easier to Segway in to this final stage which would definitely take 2-3 descriptive paragraphs to cover.
<span>In the presence of oxygen, one glucose molecule has the energy to make up to 38 ATP. The ATP production is determined by the following steps, (-2 ATP) glycolysis preparatory phase, (7-9 ATP) glycolysis pay-off phase, (5 ATP) oxidative decarboxylation of pyruvate and (20 ATP) Krebs cycle. One glucose which has 38 ATP hence was the summation of all the process mentioned that took place. All these process take place under the cellular function of cellular respiration.<span>
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Most organisms are Diploid, and as a result, they will have received 2 copies of the chromosomes, or sets of chromosomes, from both their parents. This they will have 2 sets of Genes that will perform almost exact same process, except with different phenotypes.
These chromosomes need to be homologous, in order for new alleles and other genetic combinations to be made.
They are both in the same cell