Final answer:
Gregor Mendel studied pea plants because they were true-breeding, had observable traits with distinct variations, matured quickly, and could be cultivated in large quantities to yield statistically significant data.
Step-by-step explanation:
Gregor Mendel selected pea plants (Pisum sativum) for his groundbreaking experiments on heredity because they exhibited several key characteristics that made them ideal for studying inheritance. One such reason is that pea plants are true-breeding, which means they consistently produce offspring that resemble the parent plant when self-fertilized. This trait was crucial for Mendel's work as it prevented the appearance of unexpected characteristics that could complicate his genetic analyses. Additionally, garden peas have several observable traits with two common values, like seed shape and flower color, making it easy to track their inheritance patterns. The pea plants' ability to grow to maturity within a single season allowed Mendel to study multiple generations in a short timeframe, while the high volume of peas that could be cultivated at once ensured that his observations were statistically significant and not due to chance.