Question

Homozygous tall (TT) pea plants look the same as heterozygous tall (Tt) pea plants. Formulate a pollination experiment to identify whether a tall pea plant is homozygous or heterozygous. Explain your answer in 4-5 sentences. Please make your answer simple, coherent, and intended for 9th grade.

Answer 1

To determine if a tall pea plant (TT or Tt) is homozygous (TT) or heterozygous (Tt), you can perform a simple cross-pollination experiment with a known homozygous recessive plant (tt), which is short. First, take the tall pea plant you want to test and pollinate it with the short pea plant. If the offspring from this cross are all tall, the original tall plant must be homozygous (TT). However, if you get a mix of tall and short offspring, then the original tall plant is heterozygous (Tt), since the Tt plant can pass on the recessive t allele to produce short plants. This method helps you identify the genotype of the tall plant by observing the traits of the next generation.