Question

What are the 2 types of mutation?

Answer 1

Mutations are sudden changes in genotype, involving qualitative and quantitative alternations in the genetic material itself which change the phenotype of an organism. Mutations may occur at a stage in the development of an organism. Mutations may take place either in somatic cells or in the germinal tissue.

Complete answer:
Mutations are of two types:
A. Chromosomal mutations= Chromosomal aberration (intergenic changes).
This may result in an alteration in the number of nucleotides or position of nucleotides in genetic material.
Types of chromosomal mutations:
a. Change involving, changes in the structure of chromosome:
Gene disturbance is an intergenic level not involving their internal structure. This type of modification of chromosomes involves the rearrangement of genes or the loss of genes. These changes may be of the following types:
1. Deficiency
2. Duplication
3. Translocation
4. Inversion
b. Variation in chromosome number :
The somatic chromosome number of any species, whether diploid or polyploid, is designated as 2n, and the chromosome number of the gamete is denoted as n.
Variation in chromosome number can be of two types:
1. Euploidy: When variation of chromosome number is through an increase in one or more complete sets of chromosomes or genomes. It is further categorized into monopoly, diploidy, polyploidy.
2. Aneuploidy: When chromosome number is not an exact multiple of the basic number but is more or less than the base (diploid) number.

B. Gene mutation= point mutation (intragenic changes)
Gene mutation or point mutation refers to the alteration of a small segment of DNA (either Single nucleotide or a pair of nucleotides).
Point mutations are of the following types:
a. Frameshift mutation: Insertion or deletion of a base pair or pairs in DNA are referred as
Frameshift mutation because in this shift the reading frame of codons from the change on
Ward.
b. Substitution: These are gene mutations where one or more base pairs are substituted by others. It is further divided into various types: transition mutations, transversion. Mutations, base analog substitution.

Note:
All mutations do not cause phenotypic changes in a cell organism. Following are the two types of base pair mutations that change the DNA but do not alter the visible phenotype of an organism: silent mutation and neutral mutation. In silent mutation a base pair changes in an alleles’ codon that produces no change in the amino acid sequence of the protein. In the case of neutral mutation, a base pair substitution in an allele’s codon produces a different amino acid in the protein but this amino acid does not change the function of the protein.