NURSING ANM AND GNM

Detailed explanation-1: -Reverse mutation, also called reversion, denotes any mutational process or mutation that restores the wild-type phenotype to cells already carrying a phenotype-altering forward mutation. Forward mutations confer a gene sequence and phenotype different from that conferred by the wild-type gene.

Detailed explanation-2: -Auxotrophs are a group of organisms that lost the ability to synthesize certain substances required for their growth owing to the presence of mutations. Compared to the wild type strain, the auxotrophic mutants cannot grow in minimal medium if the corresponding nutrients are not supplied.

Detailed explanation-3: -1. Replica Plating Technique: Lederberg and Lederberg (1952) have given replica plating technique. This technique is used to detect auxotrophic mutants which differentiates between mutants and wild type strains on the basis of ability to grow in the absence of an amino acid.

Detailed explanation-4: -They cannot grow unless their environment contains some specific nutrient – an amino acid, a vitamin, a nucleic acid precursor – that is not required by the prototroph.