Viruses aren't able to respond to stimuli when outside of a host cell because outside host cells, viruses are dormant and sometimes even considered dead. Only when a virus starts reproducing in a cell can it weakly respond to stimuli.
**Viruses they do not respond to stimuli when they are outside host. **
This is because outside viruses and hosts are being dormant. They can be even be considered as dead.
Virus can only respond to stimuli only when they start reproducing in a cell.
Viruses do not respond to stimuli to maintain homeostasis when they are outside a host, as they are inactive and dormant. They only become active and interact with their environment when infecting a host cell, but their processes are not equivalent to living organisms maintaining homeostasis. Therefore, viruses operate differently from living organisms.
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