Explain how the behavior of homologous chromosomes in meiosis parallels Mendel's law of segregation for autosomal alleles D and d. During which stage of M phase do these two alleles segregate from one another?

Key Concepts

Homologous Chromosomes

Homologous chromosomes are pairs of chromosomes in a diploid organism, one inherited from each parent. They carry the same genes at the same loci but may have different alleles. During meiosis, these chromosomes undergo pairing and recombination, which is crucial for genetic diversity. Understanding their behavior is essential for grasping how alleles segregate during gamete formation.

Mendel's Law of Segregation

Mendel's Law of Segregation states that during the formation of gametes, the two alleles for a trait separate from each other so that each gamete carries only one allele for each gene. This principle explains how offspring inherit one allele from each parent. The law is illustrated during meiosis when homologous chromosomes are separated, ensuring that each gamete receives only one allele from each gene pair.

Meiosis and M Phase

Meiosis is a specialized type of cell division that reduces the chromosome number by half, resulting in four haploid gametes. The segregation of alleles occurs during the M phase of meiosis, specifically in Anaphase I, when homologous chromosomes are pulled apart to opposite poles of the cell. This stage is critical for ensuring that each gamete receives a unique combination of alleles, reflecting Mendel's law.