MDCAT Biology MCQ #340

A glucose molecule enters the cytosol to begin glycolysis and is immediately phosphorylated. Which enzyme is responsible for this initial activation step?

MDCAT Biology MCQ #340

  1. Question 1

    Q1. A glucose molecule enters the cytosol to begin glycolysis and is immediately phosphorylated. Which enzyme is responsible for this initial activation step?

    • A) Hexokinase
    • B) Phosphofructokinase
    • C) Pyruvate kinase
    • D) Aldolase

    Answer: Hexokinase

    Explanation: Hexokinase catalyzes the first ATP-consuming step in glycolysis. Phosphofructokinase is tempting but it performs the second phosphorylation on fructose-6-phosphate.