Question

Does a mutation need to happen on both homologous chromosomes to be inherited?

Answer 1

Answer: No
Explanation:
Homologous chromosomes = A pair of chromosomes that are similar in their size, centromere location, and gene order.
Alleles of a gene are located at similar locations on homologous chromosomes.
Diploid organisms contain two sets of genomes. Each set is inherited from one parent (Maternal and paternal). i.e. in a homologous pair of chromosomes, one chromosome is inherited from the mother and the other from the father.

During meiosis-I, homologous chromosomes are separated. Each chromosome is transmitted to one cell. If there is a mutation in the paternal chromosome, half of the gametes acquire that mutation.
If there is a mutation in both chromosomes of a homologous pair, all gametes acquire the mutation.