Which term describes an infectious agent that consists of a protein coat surrounding a nucleic acid and relies on living cells to replicate?

Which term describes an infectious agent that consists of a protein coat surrounding a nucleic acid and relies on living cells to replicate?

• A. Organ
• B. Virus
• C. Protozoan
• D. Prion

Answer: (B)

A virus is an infectious agent that fits this description. It has a genome made of nucleic acid (DNA or RNA) enclosed in a protein coat, and it cannot replicate on its own. Instead, it must enter a living cell and hijack the cell’s machinery to produce new virus particles, making it an obligate intracellular parasite. An organ is not an infectious agent at all. A protozoan is a living cellular organism capable of replication on its own, not just a nucleic acid wrapped in a coat. A prion is just a misfolded protein with no nucleic acid, so it lacks the genetic material and protective coat described.

A virus is an infectious agent that fits this description. It has a genome made of nucleic acid (DNA or RNA) enclosed in a protein coat, and it cannot replicate on its own. Instead, it must enter a living cell and hijack the cell’s machinery to produce new virus particles, making it an obligate intracellular parasite.

An organ is not an infectious agent at all. A protozoan is a living cellular organism capable of replication on its own, not just a nucleic acid wrapped in a coat. A prion is just a misfolded protein with no nucleic acid, so it lacks the genetic material and protective coat described.