Final Answer:
In anaerobic conditions, what will deplete quickly is Glucose. Thus the correct option is B.
Step-by-step explanation:
Anaerobic conditions refer to environments where oxygen is lacking or insufficient. In such settings, cells rely on anaerobic respiration to generate energy. The primary substrate for anaerobic respiration is glucose. During anaerobic metabolism, glucose undergoes glycolysis to produce energy in the absence of oxygen. As cells continue to metabolize glucose without the presence of oxygen, the supply of available glucose will deplete rapidly, making option B the correct choice.
In glycolysis, one molecule of glucose (C₆H₁₂O₆) is broken down into two molecules of pyruvate. The chemical equation for glycolysis is \(C₆H₁₂O₆ + 2 ADP + 2 Pᵢ + 2 NAD⁺ → 2 C₃H₄O₃ + 2 ATP + 2 NADH + 2 H⁺\). The process yields a net gain of two molecules of ATP (adenosine triphosphate), which is the cell's primary energy currency. However, in the absence of oxygen, these pyruvate molecules may undergo fermentation, leading to the production of lactic acid or ethanol. The swift depletion of glucose under anaerobic conditions highlights its crucial role as the primary energy source in the absence of oxygen.
In summary, in anaerobic conditions, glucose is rapidly consumed and depleted as cells resort to anaerobic respiration to meet their energy needs. This emphasizes the significance of glucose as a key substrate in cellular metabolism when oxygen is limited.