General Virology: Structure and Function

Nucleic Acids in Viruses

• Viruses can contain either DNA or RNA as their genomic material.
• RNA viruses may be single-stranded (ssRNA) or double-stranded (dsRNA).
• DNA viruses can also be single-stranded (ssDNA) or double-stranded (dsDNA).

Capsid Function

• The capsid serves as a protective protein coat for the viral genome.
• It facilitates the attachment and entry of the virus into host cells.
• The capsid is crucial in determining the virus's shape and symmetry.

Nucleocapsid Symmetry in Adenovirus

• Adenoviruses possess an icosahedral symmetry in their nucleocapsid structure.
• This symmetry contributes to the stability and efficiency of the viral particle.

Enveloped Viruses

• Viruses like HIV, Influenza, and Herpes are surrounded by a lipid membrane called an envelope.
• The envelope is derived from the host cell membrane during the budding process.
• Envelopes are crucial for the virus's ability to infect host cells and evade the immune system.

Metabolic Characteristics of Viruses

• Viruses are metabolically inactive outside of a host organism and do not carry out metabolic processes independently.
• They require a host cell's machinery for replication and protein synthesis.
• Viruses can be considered obligate intracellular parasites.

Test your knowledge of virology with this quiz covering the structure and function of viruses, including their genomes, capsids, and envelopes. Learn about the smallest infectious agents and their detection using electron microscopes.