A virus with a lipid envelope is typically enveloped due to acquisition from what source?

• A. Host cell membrane
• B. Viral capsid alone
• C. Bacterial cell wall
• D. Nuclear envelope

Answer: (A)

Lipid envelopes come from the host cell membrane during viral budding. As the virus exits the cell, it steals a patch of the host’s lipid bilayer, which becomes the envelope and includes viral glycoproteins. This makes the envelope a feature derived from the host cell rather than from the viral capsid itself, and not from the bacterial cell wall. While some viruses can acquire envelopes from internal membranes like the nuclear or endoplasmic reticulum membranes in certain contexts, the common situation taught is budding through the host cell plasma membrane.