In: Biology
List and describe the general phases in animal virus multiplication. Contrast the multiplication of an enveloped virus with that of a naked virus.
The phases of animal virus multiplication are:
Adsorption- Binding of virus to specific molecule on host cell
Penetration- Genome enters host cell
Uncoating- Viral nucleic acid is released from capsid
Synthesis- Viral components are produced
Assembly-New viral particles are constructed
Release-Assembled viruses are released by budding (exocytosis) or cell lysis.
Enveloped viruses may enter differently than naked viruses. Some viruses inject their nucleic acid, whereas others must also ensure that a virus-associated RNA or DNA polymerase enters the cell. Some naked viruses undergo a major change in capsid structure on adsorption to plasma membrane, so that their nucleic acids are released into the cytoplasm, some enveloped viruses engulfed by receptor-mediated endocytosis to form coated vesicles, which fuse with lysosomes. Lysosomal enzymes may help with uncoating. Naked virions usually released by host cell lysis, enveloped viruses bud out through cell membrane.