Which of the following is a typical virus component?

• A. Nucleic acid, capsid, envelope
• B. Mitochondria
• C. Chloroplasts
• D. Ribosomes

Answer: (A)

Viruses are simple infectious particles built around a genome and a protective protein shell. The essential parts you’ll commonly see are the nucleic acid genome and a capsid that encases it. Many viruses also have a lipid envelope surrounding the capsid, which is derived from the host cell membrane and studded with viral proteins. So a set that includes nucleic acid, a capsid, and an envelope captures the typical architecture of many viruses.

Mitochondria and chloroplasts are energy-producing and photosynthetic organelles found inside certain cells, not components of viruses. Ribosomes are the cellular machinery for protein synthesis; while viruses hijack host ribosomes to make their proteins, virions themselves do not carry ribosomes as part of their structure.