Q. The major cause of evolution of genes and proteins is :
(a) Point mutation
(b) Chromosomal aberration
(c) Sexual reproduction
(d) Gene duplication and divergence
Solution :
Correct option : A Point mutation refers to change in single nucleotide base in DNA. This results in change of sequence of mRNA and ultimately polypeptide chain formed by translation. Proteins are made up of polypeptide chains. If this change allows the organism to survive longer than the others in the population without the mutation, it gives the mutated organism a higher chance to pass on its genes. If this variation is disadvantageous for survival, organisms will have lower chances to pass on its gene. This goes on throughout different generations which leads to evolution. So, the correct answer is ‘Point mutation’
