Question

select all the correct answers. a particular plant has two alleles that control the length of its stem. t represents the dominant allele that codes for a tall stem, and t represents the recessive allele that codes for a short stem. based on the punnett squares, which two statements are true about the genotype of the plants stem length? first generation t t t tt tt t tt tt second generation t t t tt tt t tt tt plants with short stems are homozygous for that trait. plants with tall stems are always homozygous for that trait. both parent plants in second generation are heterozygous. both parent plants in second generation are homozygous.

Explanation:

1. Analyze the Punnett - square for stem - length inheritance. Homozygous plants have two identical alleles (TT or tt), and heterozygous plants have two different alleles (Tt).
2. In the first - generation cross (TT x tt), all offspring are Tt (heterozygous). In the second - generation cross (Tt x Tt), the genotypes are TT : Tt : tt in a 1:2:1 ratio. So, not all second - generation parent plants are homozygous or heterozygous. Plants with short stems (tt) are homozygous for the short - stem trait, and plants with tall stems can be either homozygous (TT) or heterozygous (Tt).

Answer:

Plants with short stems are homozygous for that trait.
Plants with tall stems are always homozygous for that trait. (This statement is false as tall - stemmed plants can be Tt, which is heterozygous)
Both parent plants in second generation are homozygous. (This statement is false as there are Tt plants in the second - generation cross)
Both parent plants in second generation are heterozygous. (This statement is false as there are TT and tt plants possible in the second - generation along with Tt)

The correct statement is: Plants with short stems are homozygous for that trait.