Question

Which parental plants did Mendel select for his initial crosses to study the law of dominance?

Options

• Partially dwarf and completely tall plants

• Heterozygous tall (Tt) and heterozygous dwarf plants

• Pure-breeding tall (TT) and pure-breeding dwarf (tt) plants

• Random plants of mixed heights

Answer 1

Mendel selected pure-breeding plants as parents—tall (TT) and dwarf (tt)—both of which were true-breeding, meaning they consistently produced only their own phenotype across generations, ensuring clear contrasting traits.