Final answer:
Gregor Mendel studied seven different characteristics in pea plants, such as flower color, seed shape, and seed color, identifying the basic laws of inheritance through his experiments with nearly 30,000 pea plants.
Step-by-step explanation:
The Austrian monk Gregor Mendel conducted experiments on pea plants to understand the principles of inheritance. During his first set of experiments, Mendel focused on single characteristics of pea plants, such as flower color. He began by cross-pollinating purple- and white-flowered plants. Proceeding with his research, Mendel eventually studied seven different characteristics in pea plants. These included seed shape (smooth vs. wrinkled), seed color (yellow vs. green), flower color (purple vs. white), and plant height (tall vs. short). He meticulously analyzed the patterns of inheritance and discovered that traits are inherited discretely rather than through blending, as was widely believed at the time.
Mendel's experiments involved close to 30,000 pea plants, which allowed him to observe consistent ratios in the inheritance of these traits. His findings led to the formulation of the laws of inheritance, including the Law of Segregation and the Law of Independent Assortment. These findings were achieved by meticulous tracking of the pea plants' characteristics across several generations, resulting in a foundation for modern genetics.