During Penetration of E. Coli by the T4 Phage

Question

During penetration of E. coli by the T4 phage,
A) lysozyme is used to allow entry of the phage capsid.
B) the tail acts as a "hypodermic needle," injecting the phage DNA into the cell.
C) the protein fibers digest a hole in the cell wall.
D) the bacterial receptor molecules open a hole through the cell wall.
E) the intact phage enters the host by endocytosis.

Accepted Answer

The T4 phage has a tail that acts as a "hypodermic needle" to inject the phage DNA into the host E. coli cell. This is called the injection or penetration phase of the phage life cycle. The tail sheath contracts, forcing the tail core through the outer membrane and cell wall, and the DNA is injected through the core into the bacterial cytoplasm.