NEET BIOLOGY

Detailed explanation-1: -Viral replication within a living cell always produces changes in the cell, sometimes resulting in cell death and sometimes slowly killing the infected cells. There are six basic stages in the virus replication cycle: attachment, penetration, uncoating, replication, assembly, and release.

Detailed explanation-2: -Effects on Cell Biochemistry: Many viruses inhibit the synthesis of host cell macromolecules, including DNA, RNA, and protein. Viruses may also change cellular transcriptional activity, and protein-protein interactions, promoting efficient production of progeny virus.

Detailed explanation-3: -Most viral infections eventually result in the death of the host cell. The causes of death include cell lysis, alterations to the cell’s surface membrane and various modes of programmed cell death. Some viruses cause no apparent changes to the infected cell.

Detailed explanation-4: -The lytic cycle leads to the death of the host, whereas the lysogenic cycle leads to integration of phage into the host genome. Bacteriophages inject DNA into the host cell, whereas animal viruses enter by endocytosis or membrane fusion.

Detailed explanation-5: -Then the viral genome hijacks the host cell’s machinery, forcing it to replicate the viral genome and produce viral proteins to make new capsids. Next, the viral particles are assembled into new viruses. The new viruses burst out of the host cell during a process called lysis, which kills the host cell.