List the four properties that define a virus. What is a virion?

Verified step by step guidance

1. Identify the four key properties that define a virus: 1) Viruses are acellular, meaning they lack cellular structure. 2) They contain either DNA or RNA as their genetic material, but not both. 3) Viruses are obligate intracellular parasites, requiring a host cell to replicate. 4) They have a protein coat, called a capsid, that encases their genetic material.
2. Understand that a virion is the complete, infective form of a virus outside a host cell, with a core of RNA or DNA and a capsid.
3. Recognize that the capsid is made up of protein subunits called capsomeres, which protect the viral genetic material and aid in its delivery into host cells.
4. Note that some viruses have an additional lipid envelope derived from the host cell membrane, which can contain viral proteins that help the virus attach to and enter host cells.
5. Remember that the study of viruses, their structure, and their life cycle is crucial for understanding how they cause disease and for developing antiviral therapies.

Key Concepts

Properties of Viruses

Viruses are defined by four key properties: they are acellular, meaning they lack cellular structure; they cannot reproduce independently and must infect a host cell to replicate; they contain genetic material, either DNA or RNA, encased in a protein coat; and they exhibit specificity, targeting particular host cells or organisms.

Virion Structure

A virion is the complete, infectious form of a virus outside a host cell. It consists of genetic material (either DNA or RNA) surrounded by a protective protein coat called a capsid, and in some cases, an additional lipid envelope. The structure of a virion is crucial for its ability to infect host cells and initiate the viral replication cycle.

Viral Replication

Viral replication is the process by which a virus reproduces within a host cell. This involves several steps: attachment to the host cell, entry, uncoating of the viral genome, replication of the viral components, assembly of new virions, and release from the host cell. Understanding this process is essential for studying viral behavior and developing antiviral therapies.