<span>When a virus enters the cell of a human body it can start hosting inside the cell and reproduce itself. A virus can easily affect the body at the same time the immune system would activate to fight the viruses. Medication is needed to prevent it from spreading and worsen.</span>
Answer: According to Darwin theory of evolution the struggle for existence is considered as major part for competition among living things.
Explanation:
Coexisting species that belong to the same genera compete for same kind of resources for their survival. Some phenotypic variations gives an survival advantage over others. The superior ones dominate the inferior ones and compete for resources. The one who receives the resources like mates, food, shelter, and others the chances of survival also increases considerably.
