Question

Describe how mutations lead to genetic variations

Answer 1

mutation is the source of genetic variation because say you have a population of all homozygous dominant genes: AA . and then a recessive gene appears due to a mutation: Aa. so if AA and Aa reproduce, their offspring will be : AA,AA,Aa,Aa. and as they reproduce over and over again, the number of heterozygous individuals will increase. so "variance" in the gene pool of that population will increase, because originally they were all homozygous, but now(due to a genetic mutation) some heterozygous individuals exist. these hetero individuals will increase over time, but ONLY if this mutation doesn't cause the individual to have a disadvantage such as low fertility, in which case the heterozygous will be at a very low percentage or will disappear all together.
i hope that answers your question