Which of the following are the main inputs required for the process of fermentation in cells?

• A. Glucose and NADextsuperscript{+}
• B. Oxygen and ATP
• C. Pyruvate and FADHextsubscript{2}
• D. Carbon dioxide and water

Answer: (A)

Verified step by step guidance

1. Understand the process of fermentation: Fermentation is an anaerobic process (does not require oxygen) that allows cells to produce energy in the absence of oxygen by regenerating NAD⁺, which is essential for glycolysis to continue.
2. Identify the main inputs for fermentation: The process begins with glucose, which is broken down during glycolysis to produce pyruvate. NAD⁺ is also required to accept electrons during glycolysis.
3. Eliminate incorrect options: Oxygen and ATP are not required for fermentation because fermentation occurs in the absence of oxygen, and ATP is a product, not an input. Pyruvate and FADH₂ are not inputs for fermentation; pyruvate is an intermediate, and FADH₂ is involved in aerobic respiration. Carbon dioxide and water are products of aerobic respiration, not fermentation.
4. Focus on the correct inputs: Glucose is the primary energy source, and NAD⁺ is necessary to maintain glycolysis by accepting electrons during the process.
5. Conclude that the correct answer is Glucose and NAD⁺, as these are the main inputs required for fermentation in cells.