Which of the following pathways is primarily responsible for the breakdown of glucose to produce ATP in the cytoplasm of a cell?

• A. Glycolysis
• B. Calvin cycle
• C. Beta-oxidation
• D. Urea cycle

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the context of the question. The problem is asking about the metabolic pathway responsible for breaking down glucose to produce ATP in the cytoplasm of a cell. This requires knowledge of cellular respiration and metabolic processes.
2. Step 2: Recall the key metabolic pathways. Glycolysis, Calvin cycle, beta-oxidation, and urea cycle are all distinct processes. Glycolysis is specifically involved in glucose breakdown, while the others serve different functions (e.g., Calvin cycle is part of photosynthesis, beta-oxidation breaks down fatty acids, and urea cycle is involved in nitrogen waste removal).
3. Step 3: Focus on glycolysis. Glycolysis is the pathway that occurs in the cytoplasm and involves the enzymatic breakdown of glucose into pyruvate, producing ATP and NADH as energy carriers. This process does not require oxygen and is the first step in cellular respiration.
4. Step 4: Eliminate incorrect options. The Calvin cycle occurs in chloroplasts during photosynthesis, beta-oxidation occurs in mitochondria and breaks down fatty acids, and the urea cycle occurs in the liver to process nitrogen waste. None of these are responsible for glucose breakdown in the cytoplasm.
5. Step 5: Conclude that glycolysis is the correct pathway for the breakdown of glucose to produce ATP in the cytoplasm of a cell.