Viruses ~Ch. 13 (The Condensed Version)

Review…broader microbe categories

• Microbes can be divided into those that are either:

• Truly cellular (bacteria, archaea, algae, protozoa, and fungi) and • Those that are acellular (viruses and prions)

• Cellular microbes can be divided into those that are:

• prokaryotic (bacteria and archaea) and those that are

• eukaryotic (algae, protozoa, and fungi)

Some general key points on viruses

• Complete virus particles are called virions.

• Most viruses range from 10-300 nm in diameter.

• Viruses infect humans, animals, plants, fungi, protozoa, algae, and bacterial cells….also some viruses can infect other viruses!

• A typical virion consists of

• A genome of either DNA or RNA (and this is either ds or ss)

• A capsid (protein coat) that surrounds this genome

•The capside is composed of protein units called capsomeres

• Some viruses (enveloped viruses) have an outer envelope.

DNA or RNA: may be ds or ☠

Explain this

A) A is an enveloped virus- stole lipid memebrane from the host cell

B) Is a non enveloped virus. Capsomere = the proteins

Viral Replication

A key feature of viral replication is that viruses need a host to reproduce.

• And they are released from the host by lysing or by budding.

• Those that escape by budding become enveloped viruses.