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Biology

Biology · Enzymes

Work through this past-paper style MCQ, then read the full explanation. Practice more biology questions on mMCQ with adaptive drills and topic analytics.

Question

Enzyme succinate dehydrogenase converts succinate into: 

Options
  • A

    Malate 

  • B

    Malonic acid 

  • C

    Citrate 

  • D

    Fumarate  

Explanation

In Krebs cycle, an enzyme called succinate dehydrogenase acts on its substrate, succinate, and converts it into product fumarate. 

Malate is produced when a molecule of water combines with fumerate. This option is incorrect.

This option is incorrect. Malonic acid is not a naturally occurring intermediate of Krebs cycle.

Citrate is produced when Acetyl-CoA combines with oxaloacetate a four carbon compound. This option is incorrect. 

An enzyme called succinate dehydrogenase converts succinate into fumerate in Krebs cycle. This option is correct.

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Tagged under Biology · Enzymes