How does the law of segregation apply to Mendelian inheritance?

The law of segregation applies to Mendelian inheritance by dictating that alleles separate during gamete formation.

In more detail, the law of segregation, also known as Mendel's First Law, is a fundamental principle of genetics proposed by Gregor Mendel in 1865. This law states that every individual organism contains two alleles for each trait, and that these alleles segregate (separate) from each other during the formation of gametes. Each gamete then contains only one allele of each pair.

In the context of Mendelian inheritance, this law explains how traits are passed from parents to offspring. When an organism reproduces, it passes on one of these alleles to its offspring. If the two alleles of an inherited pair differ from each other (i.e., they are heterozygous), then one is dominant and the other is recessive. The dominant allele will mask the presence of the recessive allele, meaning that the trait associated with the dominant allele will be expressed.

For example, consider a pea plant that is heterozygous for seed colour, with one allele for yellow seeds (the dominant allele) and one for green seeds (the recessive allele). According to the law of segregation, these two alleles will separate during gamete formation. The resulting gametes will each carry one allele for seed colour - either yellow or green. When these gametes are involved in fertilisation, the resulting offspring will inherit one allele from each parent, which will determine the colour of their seeds.

The law of segregation is a fundamental principle of Mendelian inheritance, explaining how traits are passed from one generation to the next. It provides a framework for understanding the distribution of traits in a population, and forms the basis for the study of genetics.