Question

1. You are taking this test while breathing in molecular oxygen (O₂) and breathing out carbon dioxide (CO₂). The CO₂ arises from:

Select one:

a. Glucose in glycolysis.

b. Redox reactions involving NAD⁺ and NADH in the mitochondria.

c. More than one of the above answer options is correct.

d. None of the above answer options are correct.

e. The oxidation of small molecules by the krebs (or citric acid) cycle.

2. Water:

Select one:

a. More than one of the other answer choices is correct.

b. None of the other answer choices are correct.

c. Is the final electron acceptor of the electron transport chain.

d. Has electrons that are distributed around the molecule in a symmetric manner.

e. Can dissolve both ionic and non-polar substances.

Answer 1

Ans1) e) The oxidation of small molecules by the krebs (or citric acid) cycle.

Explaination: In kreb cycle one Co2 molecule release during oxidative decarboxylation of isocitrate and another C02 molecule releases in next step where alpha ketoglutarate undergo oxidative decarboxylation and produce succinyl coA and release of carbon dioxide molecule.

Ans2)b) none of the other ans choices are correct

Explaination:

Water is a polar molecules so electron distribution is assymmetric and water can dissolve polar molecules not non polar molecules.

Water is the final product of ETS and O2 is the final acceptor of electron in electron transport chain.