Krebs cycle takes place in

Options

A. Vesicles of E.R.
B. Mitochondria
C. Dictyosomes
D. Chloroplasts.

Answer

**Step-by-Step Solution:**

1. **Understanding the Krebs Cycle**: The Krebs cycle, also known as the citric acid cycle, is a crucial metabolic pathway that plays a significant role in cellular respiration. It is involved in the oxidation of acetyl-CoA, which is derived from carbohydrates.

2. **Location of the Krebs Cycle**: The Krebs cycle takes place in the mitochondria of the cell. Specifically, it occurs in the mitochondrial matrix, which is the innermost compartment of the mitochondria.

3. **Role of Pyruvate**: During glycolysis, glucose is broken down into pyruvate. This pyruvate is then converted into acetyl-CoA, which is the substrate that enters the Krebs cycle.

4. **Formation of Citrate**: In the Krebs cycle, acetyl-CoA combines with oxaloacetate to form citrate, which is the first step of the cycle.

5. **Energy Production**: Each pyruvate molecule can produce a significant amount of ATP through the Krebs cycle. One pyruvate can yield approximately 15 ATP, and since two pyruvate molecules are produced from one glucose molecule, the total ATP production can reach around 30 ATP.

6. **Conclusion**: Based on the information gathered, the correct answer to the question "Krebs cycle takes place in" is **mitochondria**.

**Final Answer**: The Krebs cycle takes place in the mitochondria.

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