Learn: lect 9 pt 2

What can some single-stranded RNA viruses be?

Some single-stranded RNA are positive or negative.

What can animal viruses be made of?

Animal viruses can be naked or enveloped.

What are the stages in infection of a host cell with animal viruses?

1) Adsorption, 2) Penetration and uncoating, 3) Synthesis of new viral components, 4) Self assembly of new viruses, 5) Release of new viruses.

What is Stage 1 — Adsorption?

Adsorption is the sticking of a virus to receptors on the host.

What happens during adsorption?

The virus sticks to receptors on the host.

What is Stage 2 — Penetration and uncoating?

Entry of a virus into a host and release of the virus nucleic acid into the host cell.

What happens during penetration and uncoating?

The virus enters the host and releases the virus nucleic acid into the host cell.

What is Stage 3 — Synthesis of new viral components?

Synthesis of new viral components, including proteins and nucleic acids.

What happens during synthesis of new viral components?

New viral components are made, including proteins and nucleic acids.

What is Stage 4 of animal virus infection?

Self assembly of new viruses.

What happens during self assembly?

New viruses self assemble.

What is Stage 5 of animal virus infection?

Release of new viruses.

What happens during the release stage?

New viruses are released.

What are the 2 groups of animal viruses?

1) Cytocidal viruses and 2) budding viruses.

What are most cytocidal viruses like?

Most cytocidal viruses are naked.

What happens with most cytocidal viruses?

Most cytocidal viruses are naked and the host cell lyses to release the viruses.

What happens to the host cell with most cytocidal viruses?

The host cell lyses to release the viruses.

What are most enveloped viruses?

Most enveloped viruses are budding viruses.

What happens with most enveloped viruses?

They are budding viruses and become enveloped as the viruses push out of the cell membrane and pick up membrane as they bud out of the cell.

How do budding viruses become enveloped?

Viruses push out of the cell membrane and pick up membrane as they bud out of the cell.

What happens to the host cell during budding?

The host cell usually remains alive during budding.

What is the key difference between cytocidal viruses and budding viruses?

Most cytocidal viruses are naked and the host cell lyses to release the viruses, while most enveloped viruses are budding viruses and the host cell usually remains alive during budding.

What are the 5 stages of infection of a host cell with an animal virus?

Adsorption → penetration and uncoating → synthesis of new viral components → self assembly of new viruses → release of new viruses.

What is the key difference between the release of cytocidal and budding viruses?

Cytocidal viruses are released when the host cell lyses; budding viruses push out of the cell membrane and pick up membrane as they bud out of the cell.

What happens to the host cell with a budding virus compared with a cytocidal virus?

The host cell usually remains alive during budding, while the host cell lyses with most cytocidal viruses.