Mendel, also known as the father of genetics, conducted experiments on pea plants in the mid-1800s. Through his observations, he made significant discoveries about the patterns of inheritance and the transmission of traits in pea plants.

a) He found that the pea plant has some traits that come in pairs:

Mendel discovered that certain traits in pea plants are inherited in a predictable manner, following specific patterns. He observed that many traits in pea plants occur in pairs and are determined by the presence of specific factors, which he later called genes. These pairs of traits can be either dominant or recessive.

- Dominant Traits: Mendel found that some traits, such as tall height, flower color, and smooth seed texture, were dominant over others. When a plant with a dominant trait was crossed with a plant having a recessive trait, the dominant trait would always be expressed in the offspring.

- Recessive Traits: Mendel also observed that some traits, such as short height, white flower color, and wrinkled seed texture, were recessive. When two plants with recessive traits were crossed, the offspring would also exhibit the recessive trait.

Mendel's experiments involved carefully controlling the cross-pollination of different pea plant varieties and tracking the traits expressed in the offspring. By meticulously recording his observations and analyzing the ratios of dominant and recessive traits in subsequent generations, he formulated the laws of inheritance.

These laws, known as Mendel's Laws of Inheritance, laid the foundation for modern genetics. They provided evidence for the existence of discrete units of inheritance (genes) and explained how traits are passed from one generation to the next.

In summary, Mendel's experiments with pea plants revealed that traits in these plants come in pairs, with some traits being dominant and others recessive. These findings were crucial in understanding the principles of inheritance and paved the way for further advancements in the field of genetics.