Answer:
Viruses are considered non-living because they lack essential characteristics of living organisms. While viruses do not show movements on their own, this does not necessarily determine their living or non-living status. Here's an explanation to help clarify:
1. Definition of life: Living organisms are generally characterized by certain features, including the ability to grow, reproduce, respond to stimuli, maintain homeostasis, and carry out metabolic processes. However, not all living organisms exhibit visible movements. For example, plants may not move significantly, yet they are considered living.
2. Lack of cellular structure: Viruses do not possess cells, which are the basic units of life. Instead, they consist of genetic material (DNA or RNA) enclosed in a protein coat called a capsid. Without cells, viruses lack the machinery necessary to carry out essential life processes.
3. Inability to carry out metabolic processes: Viruses cannot perform metabolic processes, such as respiration or digestion, on their own. They do not possess the necessary enzymes or organelles to carry out these functions. Instead, viruses rely on host cells to provide the necessary resources and machinery for replication.
4. Dependence on a host organism: Viruses are obligate intracellular parasites, meaning they rely on a host organism to complete their life cycle. They need to infect a host cell and use the cellular machinery of the host to replicate and produce new virus particles. This dependence on a host is another reason why viruses are considered non-living.