EVERYDAY SCIENCE

Detailed explanation-1: -Two principal mechanisms are involved: mutation and recombination. Alterations in the genetic material of a virus may lead to changes in the function of viral proteins. Such changes may result in the creation of new viral serotypes or viruses of altered virulence.

Detailed explanation-2: -Mutations are changes in the genetic sequence, and they are a main cause of diversity among organisms. These changes occur at many different levels, and they can have widely differing consequences.

Detailed explanation-3: -As a virus replicates, its genes undergo random “copying errors” (i.e. genetic mutations). Over time, these genetic copying errors can, among other changes to the virus, lead to alterations in the virus’ surface proteins or antigens. Our immune system uses these antigens to recognize and fight the virus.

Detailed explanation-4: -A mutation is a subtle change in the genes of the virus. Some mutations make the virus more unstable and more vulnerable. Some mutations increase rates of transmission and severity. We become concerned when mutations make the virus more deadly, more contagious or both.

Detailed explanation-5: -Concept 27 Mutations are changes in genetic information. Each DNA difference results from a mutation-ranging from single nucleotide changes, to small repeated units, to larger insertions and deletions. Some mutations generate novel changes that are starting points of evolution, and some are responsible for disease.