In his experiments with garden peas, Mendel found that one physical unit is inherited from the father and one from the mother. This provided evidence for:

Mendel's law of segregation

Explanation:

In the 1860s, Gregor Mendel discovered the principle of heredity.

He proposed a theory, which was called Mendel's law of segregation. According to this law, allele pairs either segregate or separate during gamete formation or in fertilization.

He named the dominant allele (Y) [or the male unit] and recessive allele (y) [female unit].

The dominant allele was Yellow color seed and recessive allele was green color seed.

Genotypes (YY) and (Yy) gametes to form yellow color seeds, and (yy) genotypes gametes green color seed.