What is one critical factor Mendel needed to determine through his experiments?

To understand Mendel's experiments effectively, it's essential to recognize that determining the genetic background of the parent plants was crucial for his studies on inheritance. By selecting specific pea plant varieties with distinct traits, Mendel could predict how these traits would be passed on to offspring. The concept of dominant and recessive traits emerged from carefully playing with the genetic backgrounds of the parent plants he chose.

Mendel's work relied on the idea that traits are inherited based on their genetic composition. His meticulous selection of purebred parent plants allowed him to observe how traits manifested in their progeny, leading to the establishment of the foundational principles of heredity. This genetic background provided the necessary variability to analyze the inheritance patterns he was investigating, such as in height or color. Understanding these genetic backgrounds enabled him to frame his laws of inheritance, which are fundamental to the field of genetics today.