A. Potassium oxide
B. Calcium chloride
C. Magnesium nitride
D. Sodium hypochlorite
E. Potassium nitrate
Oxygen gas was most likely absent from Earth's primitive atmosphere. The current theory is that the Earth's early atmosphere was composed of mainly carbon dioxide and methane due to the high volcanic activity. Cyanobacteria and their use of photosynthesis was what caused earth's atmosphere to become oxygen enriched.
I hope that helps.
Answer:
The answer is pyruvate → lactate
Explanation:
In the reaction of glycolysis, glucose breaks down to form pyruvate yielding ATP and NADH.
Under or during strenuous exercise, which is an anaerobic condition, lactate is formed by the reoxidization of NADH and the conversion of pyruvate to lactate.