A Mendel's law that states that the pairs of homologous chromosomes separate in meiosis so that only one chromosome from each pair is present in each gamete is known as?

• A. Law of Segregation
• B. Law of Independent Assortment
• C. Chromosome Theory of Inheritance
• D. Law of Crossing Over

Answer: (A)

This principle is Mendel's law of segregation: during meiosis, homologous chromosome pairs separate so that each gamete receives only one chromosome from each pair. This separation occurs in the first division (anaphase I), producing haploid gametes that carry one chromosome from every homologous pair. When fertilization occurs, offspring receive one chromosome from each parent, restoring the diploid state. This idea specifically describes how alleles (on chromosomes) are divided into gametes, which is the essence of the law of segregation. The other ideas describe related concepts—independent assortment, chromosome-gene linkage, and recombination through crossing over—but none state the essential separation of homologous chromosomes into different gametes.