PATHOLOGY

Detailed explanation-1: -The nitrogenous base cytosine is converted to uracil after the loss of an amine group. Because uracil forms base-pairs with adenine, while cytosine forms base-pairs with guanine, the conversion of cytosine to uracil causes base substitutions in DNA.

Detailed explanation-2: -Frameshift Mutation A frameshift mutation in a gene refers to the insertion or deletion of nucleotide bases in numbers that are not multiples of three.

Detailed explanation-3: -A substitution mutation occurs when one base pair is substituted for another. For example, this would occur when one nucleotide containing cytosine is accidentally substituted for one containing guanine.

Detailed explanation-4: -A point mutation is a change in a single base pair of a gene. Point mutations, or single nucleotide polymorphisms (SNPs), involve only one nitrogen base change of the three nitrogen bases in a codon.