207k views
4 votes
During attachment of phage to E. coli, the phage

a) Actively seek out the bacteria.
b) Randomly bump into the bacteria.
c) Attach to proteins or carbohydrates on the bacterial surface.
d) Attach to the bacterial RNA.
e) Randomly bump into the bacteria AND attach to proteins or carbohydrates on the bacterial surface.

User Nirazlatu
by
7.4k points

1 Answer

6 votes

Final answer:

During attachment, a phage randomly bumps into E. coli and binds to specific proteins or carbohydrates on its surface. The attachment is mediated by structures such as the protein tail fibers and is highly specific. Only the phage's nucleic acid enters the host, leading to the replication of the phage and the lysis of the bacterial cell.

Step-by-step explanation:

Phages do not actively seek out bacteria but instead come into contact with them through random collisions. Once the phage encounters a bacterial cell, it will bind to specific surface receptors on the cell. This interaction is mediated by structures such as the protein tail fibers on the T4 bacteriophage, which recognizes and connects to the E. coli cell. The attachment is highly specific and often involves interactions with bacterial surface molecules like lipopolysaccharides and protein receptors. The initial contact between the phage and E. coli is followed by the insertion of its DNA into the host cell, which marks the beginning of the infection process. It's important to note that only the nucleic acid core of the phage enters the bacterial cell, while the capsid remains outside. The phage uses the host cell's machinery to replicate its DNA, produce new phage components, and eventually cause the cell to lysis, releasing new phage particles to infect other cells.

User Wjk
by
8.3k points