[Campbell Biology P.449] A new virus is discovered and extensively studied. Researchers conf... | Practice Question

A new virus is discovered and extensively studied. Researchers confirm that this virus possesses a membranous envelope. Based on the information provided in the text, which of the following is the most accurate inference regarding this virus's envelope?

  • A: It is exclusively composed of proteins encoded by the viral genome.
  • B: Its formation is independent of the host cell's cellular machinery.
  • C: It is primarily derived from the membranes of the host cell it previously infected.
  • D: Its presence typically limits the virus to infecting only bacterial cells.

Explanation

The text explicitly states that "These viral envelopes, which are derived from the membranes of the host cell, contain host cell phospholipids and membrane proteins. They also contain proteins and glycoproteins of viral origin." Therefore, the envelope is primarily derived from the host cell's membranes, incorporating some viral components. Options A, B, and D are incorrect as they contradict this understanding. The envelope is not exclusively viral proteins, its formation is dependent on host machinery to acquire host membranes , and envelopes are characteristic of many animal viruses, not typically limiting infection to bacteria.