AP BIOLOGY

Detailed explanation-1: -The first stage is entry. Entry involves attachment, in which a virus particle encounters the host cell and attaches to the cell surface, penetration, in which a virus particle reaches the cytoplasm, and uncoating, in which the virus sheds its capsid.

Detailed explanation-2: -Most productive viral infections follow similar steps in the virus replication cycle: attachment, penetration, uncoating, replication, assembly, and release.

Detailed explanation-3: -The attachment phase of replication comprises specific binding of a virus-attachment protein (or ‘antireceptor’) to a cellular receptor molecule. Virus receptors on cell surfaces may be proteins (usually glycoproteins) or carbohydrate residues present on glycoproteins or glycolipids.

Detailed explanation-4: -Step 1: Attachment: The virus attaches itself to the target cell. Step 2: Penetration: The virus is brought into the target cell. Step 3: Uncoating and Replication: The enveloped virus loses its envelope, and viral RNA is released into the nucleus, where it is replicated. Step 4: Assembly: Viral proteins are assembled.