Question

Purebred tall pea plants look the same as tall, heterozygous pea plants. Formulate a pollination experiment to identify whether a tall pea plant is purebred or heterozygous. Explain your answer in 3-5 sentences.

Answer 1

To identify if a tall pea plant is purebred or heterozygous, cross it with a dwarf homozygous recessive plant and observe if any dwarf offspring result, indicating heterozygosity.

Step-by-step explanation:

To determine if a tall pea plant is purebred (homozygous dominant) or heterozygous, a pollination experiment can be conducted by crossing the unknown tall pea plant with a dwarf pea plant that is homozygous recessive (tt). If the tall plant is purebred (TT), all of the progeny will be tall because they will all inherit at least one dominant tall allele. However, if the tall plant is heterozygous (Tt), then approximately half of the progeny will be tall (Tt) and half will be dwarf (tt) because the recessive allele from the dwarf parent can be expressed when combined with a recessive allele from the heterozygous parent. This pattern of inheritance follows Mendel's laws, where a 3:1 ratio of dominant to recessive phenotype is expected when crossing two heterozygous pea plants.