MDCAT Biology MCQ #216

Before entering the Krebs cycle, pyruvate must be modified in the link reaction. What is the correct carbon transition?

MDCAT Biology MCQ #216

  1. Question 1

    Q1. Before entering the Krebs cycle, pyruvate must be modified in the link reaction. What is the correct carbon transition?

    • A) Pyruvate (3C) to Citrate (6C)
    • B) Acetyl-CoA (2C) to Pyruvate (3C)
    • C) Pyruvate (3C) to Acetyl-CoA (2C)
    • D) Glucose (6C) to Pyruvate (3C)

    Answer: Pyruvate (3C) to Acetyl-CoA (2C)

    Explanation: The link reaction (pyruvate oxidation) converts 3-carbon pyruvate into 2-carbon Acetyl-CoA, releasing one CO2 molecule.