NEET BIOLOGY

Detailed explanation-1: -The lysogenic cycle: The phage infects a bacterium and inserts its DNA into the bacterial chromosome, allowing the phage DNA (now called a prophage) to be copied and passed on along with the cell’s own DNA.

Detailed explanation-2: -The lysogenic cycle, or non-virulent infection, involves the virus assimilating its genome with the host cell’s genome to achieve replication without killing the host. Figure 1. Example structure of a bacteriophage. In order to reproduce, phage must first enter the host cell.

Detailed explanation-3: -Uncoating: The viral capsid is removed and degraded by viral enzymes or host enzymes releasing the viral genomic nucleic acid. 4. Replication: After the viral genome has been uncoated, transcription or translation of the viral genome is initiated.

Detailed explanation-4: -During the lysogenic cycle, instead of killing the host, the phage genome integrates into the bacterial chromosome and becomes part of the host. The integrated phage genome is called a prophage. A bacterial host with a prophage is called a lysogen.

Detailed explanation-5: -The first stage, attachment, involves viral proteins binding to the host cell surface. There, they interact with receptors specific to them and their host cells. The specificity of viral attachment is a key decider of the range of hosts a virus can affect. This is also known as the tropism of a virus.