In which cell organelle does the Krebs cycle take place? MCQ with Answer and Explanation

In which cell organelle does the Krebs cycle take place?
A. Stroma of chloroplast
B. Mitochondrial matrix
C. Inner mitochondrial membrane
D. Cytoplasm
Answer: Option B
Solution (By JKExamLibrary)
The Krebs cycle (citric acid cycle) occurs in the mitochondrial matrix in eukaryotes. It oxidizes acetyl-CoA to CO₂, producing NADH, FADH₂, and GTP. The inner membrane houses the electron transport chain. Glycolysis occurs in cytoplasm, the Calvin cycle in chloroplast stroma. The matrix contains the necessary soluble enzymes.

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The substance that makes the plant cell wall rigid and is a major component of wood is:
A. Lignin
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Correct Answer: Option A


Explanation:
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The plant hormone that promotes the formation of abscission layers and fruit ripening is:
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Correct Answer: Option C


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Which vitamin is essential for the absorption of calcium from the intestine?
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Correct Answer: Option D


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