Why did Mendel use true-breeding plants in his studies?

Mendel used true-breeding plants in his studies primarily to ensure that traits were expressed consistently in the offspring. True-breeding plants are those that, when self-fertilized, produce offspring that exhibit the same traits for many generations. This genetic consistency allowed Mendel to have a clear understanding of how specific traits were inherited, as there would be no variability due to mixed genetics. By starting with plants that had predictable characteristics, he could better analyze how traits were passed on from one generation to the next and observe patterns of inheritance, including the concepts of dominance and recessiveness in traits. This foundational choice was crucial for the validity of his conclusions regarding heredity.