NEET BIOLOGY

Detailed explanation-1: -Mutation and recombination drive the evolution of most pathogens by generating the genetic variants upon which selection operates. Those variants can, for example, confer resistance to host immune systems and drug therapies or lead to epidemic outbreaks.

Detailed explanation-2: -Mutation and recombination can both be defined as processes that result in changes to a genome, but they are unrelated and we must make a clear distinction between them: A mutation (Section 14.1) is a change in the nucleotide sequence of a short region of a genome (Figure 14.1A).

Detailed explanation-3: -Genetic variations can arise from gene variants (also called mutations) or from a normal process in which genetic material is rearranged as a cell is getting ready to divide (known as genetic recombination). Genetic variations that alter gene activity or protein function can introduce different traits in an organism.

Detailed explanation-4: -Genetic recombination is a process that occurs during meiosis, which is the type of cell division that produces gametes. During this process, homologous chromosomes pair up and form a unit called a tetrad. The chromosomes can then cross over and exchange genetic material, which results in new combinations of alleles.