What characteristics of a virus suggests it is alive?
A It possesses all of the requirements for life.
B It can more of its own kind by itself, and it evolves.
C It has order and can evolve.
D It is an infectious agent. A and D C and D
The correct answer and explanation is:
The correct answer is C and D: It has order and can evolve.
Viruses display some characteristics that resemble life, but not all. For instance, they possess a highly ordered structure, which is essential in the definition of living organisms. A virus is made up of genetic material (either RNA or DNA) encased in a protein coat, which allows it to maintain its structure. This order is one indication that it might be “alive.”
However, viruses lack other key features that define living organisms. For instance, they do not possess the machinery necessary for energy metabolism or cellular respiration, and they cannot reproduce on their own. They must invade a host cell and hijack the host’s cellular machinery to replicate. This dependence on a host cell for reproduction and survival means viruses are not fully self-sustaining and cannot independently carry out life processes.
Viruses can evolve, which is another key characteristic of life. Through mutations and natural selection, viruses can change over time, leading to new strains that may be more effective at infecting hosts or resisting immune defenses. This ability to evolve is a strong argument for their consideration as living entities, at least in a limited sense.
Despite having order and the ability to evolve, viruses are considered non-living by most definitions because they lack the ability to perform all life functions independently. They can be classified as infectious agents that require a host cell to propagate, which places them at the boundary between life and non-life.
In conclusion, viruses have order and can evolve, which places them on the spectrum of life, but their dependence on host cells for reproduction means they do not fully meet the criteria to be considered truly alive.