Question

Suppose that the botanist carried out the test cross described in Parts A and B and determined that the original green-pod plant was heterozygous (Gg). Which of Mendel’s findings does her test cross illustrate?

Answer 1

Answer:

Law of segregation

Explanation:

Mendel's law of segregation states that alleles of a gene get separated into gametes during meiosis. He discovered this law when he crossed a homozygous tall plant with a homozygous short plant. He noticed that all the F1 offsprings were tall. He then self-crossed the F1 offsprings to produce a phenotypic ratio of 3:1 in the F2 generation.

In this test cross, a dominant plant with green pod was crossed with a homozygous recessive plant with yellow pods. This cross was conducted to determine the genotype of the dominant parent. The result showed that the parent is heterozygous (Gg) because a 1:1 phenotypic ratio was obtained i.e. 1 Green pod plant: 1 yellow pod Plant.

This illustrates what Mendel discovered in his law of segregation that each allele will get separated into the gametes. In this case of Gg plant, G and g alleles will get separated into gametes. Although the g allele was masked but it will get separated into gametes, which will fuse with another recessive gamete from the homozygous recessive parent (gg) to produce a homozygous recessive offspring.