Final answer:
Short repeated sequences within homologous chromosomes can cause misalignments, as well as deletions, duplications, and translocations, leading to abnormalities in chromosome number. Nondisjunction and errors during meiosis can result in aneuploidy and structural rearrangements. These errors can have significant impacts on the phenotype and viability of the organism.
Step-by-step explanation:
Short repeated sequences within homologous chromosomes can cause misalignments, as well as deletions, duplications, and translocations. These errors can occur during the recombination process in meiosis, leading to abnormalities in the chromosome number. Nondisjunction, the failure of homologous chromosomes or sister chromatids to separate properly, can result in aneuploidy, which is typically lethal to the embryo. Additionally, errors that occur during prophase I of meiosis can involve the exchange of sequences between homologous chromosomes or nonhomologous chromosomes, leading to duplications or translocations.