EVERYDAY SCIENCE

Detailed explanation-1: -In the absence of the living host, the viruses may run out of food and eventually die. ☞Viruses cannot reproduce outside a living cell because they lack the cellular organisation and independent machinery which is required for the reproduction and other metabolic activities.

Detailed explanation-2: -Specifically, they are pieces of genetic material (RNA or DNA) contained in a special coating of proteins called capsids. Viruses cannot replicate unless absorbed by cells in our body. Once a virus is outside the body, its capsid starts to degrade, and the more degraded its capsid is, the less likely it is to survive.

Detailed explanation-3: -Once a virus gets into a host’s body, it travels along the surfaces of cells until its proteins begin to bind with receptors on the cells. The virus and the cells then fuse, allowing the DNA or RNA inside the virus to enter the cells, where it begins to reproduce.

Detailed explanation-4: -Since viruses are intracellular parasites, they rely on their host cells for the energy, macromolecular synthesis machinery and the work benches for genome replication and particle assembly.