Practice question

During gamete formation without crossing over between gene and centromere, chromatids remain parental, homologous chromosomes carrying different alleles remain intact. Separation of homologs in meiosis I therefore accomplishes allele segregation, reducing diploid allele pair to haploid single allele in daughter cells. Sister chromatids still identical, meiosis II merely separates sisters without altering allele content. Mitosis and cleavage are equational divisions preserving allele pair, not reductional segregation required for Mendelian 1:1 gamete output. Understanding this mechanism aids pedigree analysis, Punnett predictions, linkage mapping and appreciating evolutionary conservation across taxa.