Question

Choose the incorrect statement for cro and Q proteins.

(a) They are required for the lytic life cycle to continue

(b) Cro protein inactivates the PRM promoter

(c) The Q protein is responsible for the expression of late genes

(d) cII protein is required for the lytic life cycle to continue

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I'm obligated to ask this question of Bacteriophage Lambda in division Other Vector Systems for E of Genetic Engineering

Answer 1

Right option is (d) cII protein is required for the lytic life cycle to continue

Easy explanation: The cro and Q proteins are required for the lytic life cycle to continue and cII protein is not required for it. Cro protein inactivates the PRM promoter and the Q protein is responsible for the expression of late genes. These late genes are responsible for producing coat proteins, allowing assembly of functional phage and cell lysis.