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6 good questions on "Viruses and Their Replication - What is a Virus?"

What is a virion?

A virion is the extracellular form of a virus. It allows the virus to travel from one host cell to another. The virion also protects the genome when it is outside the host cell. Proteins on the surface of the virion help the virus to attach to the host cell.

What does a virion of all viruses include?

The virion of any virus includes a protein shell, called the capsid, and the virus genome that the capsid contains.

What is the difference between bacterial viruses and animal viruses?

Bacterial viruses are naked (no further layers), whereas animal viruses have an outer layer called the envelope that consists of a phospholipid bilayer.

How does an animal virus get the phospholipid bilayer?

It is from the host cell it was first in.

What is the inner structure plus the capsid protein called in enveloped viruses?

In enveloped viruses, the inner structure of nucleic acid and capsid protein is called nucleocapsid (the naked virus).

What are the two things a viral genome can do when inside the host cell?

The virus may replicate and destroy the host in a virulent (lytic) infection.
The virus can cause a lysogenic infection; the host cell is not destroyed but genetically altered