Crossbreeding is called monohybrid, in which the parent forms differ from each other in one pair of contrasting, alternative characters.
Examples of monohybrid crosses are experiments conducted by Gregor Mendel: crosses of pea plants that differ from each other in one pair of alternative traits: yellow and green color, smooth and wrinkled surface of the seeds (the first law of Mendel is the uniformity of hybrids of the first generation).
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