MDCAT Biology MCQ #957

Hemoglobin and myoglobin both transport oxygen but differ in complexity. What is the structural distinction between these two proteins?

MDCAT Biology MCQ #957

  1. Question 1

    Q1. Hemoglobin and myoglobin both transport oxygen but differ in complexity. What is the structural distinction between these two proteins?

    • A) Presence of iron in the heme group
    • B) Ability to bind oxygen reversibly
    • C) Secondary structure consisting of alpha-helices
    • D) The number of polypeptide chains in the molecule

    Answer: The number of polypeptide chains in the molecule

    Explanation: Hemoglobin has four polypeptide chains (quaternary). Myoglobin has only one chain (tertiary). Both contain heme groups.