The correct comparison between a virus and a unicellular organism is:
Unicellular organisms have a cell membrane made from a lipid bilayer, viruses have a protein coat.
This statement accurately differentiates the structural characteristics of unicellular organisms (like bacteria or protozoa) and viruses. Unicellular organisms are composed of one cell that typically has a cell membrane, while viruses have a protein coat (capsid) that encases their genetic material.
The other statements are incorrect:
- Both unicellular organisms and viruses can respond to stimuli, although in different ways.
- Viruses do not need energy in the traditional sense, as they are inert outside a host cell. Unicellular organisms, on the other hand, require energy to carry out metabolic processes.
- Viruses reproduce only within a host cell, while unicellular organisms can reproduce asexually on their own.