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When Gregor Mendel was teaching high school students, he noticed that plants had different traits (特征). For example, some pea plants were tall, w others were short. Mendel wondered why, so he decided to experiment.
He c the seeds (种子) that were produced. He planted these new seeds and waited for the r. He wondered whether the new plants would be of medium h. But all the plants that grew from the seeds were tall.
Mendel wanted to see what would h to the next generation (一代). He crossed the tall plants with each other in the same way he had experimented with the tall and short plants. When the n plants grew, three fourths of the plants were tall, and one fourth were short.
Mendel found out that a plant r a message from each of its parents, and that message is carried by the plant's genes (基因). For example, a pea plant gets a gene for tallness or shortness from one or both of its parents. Mendel a found out that some genes were stronger than others. The gene for tallness was stronger than the gene for shortness. So a plant would be t if it had one gene for tallness and one gene for shortness. But if a plant had two genes for shortness, it would be short.
Mendel had made a great d, but few understood it at that time. Mendel became famous only after his death.
