MDCAT Biology MCQ #82

During the infection of a bacterium by a T4 phage, how does the viral DNA overcome the rigid peptidoglycan layer of the cell wall?

MDCAT Biology MCQ #82

  1. Question 1

    Q1. During the infection of a bacterium by a T4 phage, how does the viral DNA overcome the rigid peptidoglycan layer of the cell wall?

    • A) The tail fibers secrete protease enzymes to dissolve proteins
    • B) The tail releases lysozyme to digest the bacterial cell wall
    • C) The capsid head collapses to push DNA through the membrane
    • D) The host cell undergoes endocytosis to engulf the phage tail

    Answer: The tail releases lysozyme to digest the bacterial cell wall

    Explanation: Phage lysozyme enzymatically digests a portion of the peptidoglycan layer. Tail contraction provides the mechanical force for DNA injection, but lysozyme handles the chemical barrier.