Answer:
Step-by-step explanation:
Deoxyibonucliec acid(DNA) contains the genetic constituent of an individual for a child or an individual he inherits equal proportion of genetic make up or traits from both mother and father hence, the genetic constituent of a child is never 100% mother or 100% father but a blend of the two to give a new genetic makeup that have never existed before and cannot be entirely identical with either parents but 50% identical with each parent.
Mutation is a sudden change in genome of an organism that is heritable, mutation alters the genetic constituent making it different from the original plan hence, if mutation should occur an individual could have a look that is not identical with the parent because the physical expression is the function of the genetic make up.
Chromosome crossing over effect could also alter the make up of an individual making it different from parental gene.