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Question
Explain the law of dominance using a monohybrid cross.
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Solution
The law of dominance states that when a pair of alleles or allelomorphs are combined in an F1 hybrid, only one of them expresses itself, hiding the expression of the other. A monohybrid cross was used to investigate the simultaneous inheritance of a single pair of Mendelian components. A monohybrid cross is one that considers only different versions of a single character. The feature that occurred in the F1 generation was referred to as dominant, whereas the trait that did not appear in the F1 population was known as recessive.
Thus, when a pair of alleles come together in an F1 hybrid, only one of them expresses itself, hiding the expression of the other entirely. In the above example, in the Tt - F1 hybrid (tall), only ‘T’ expresses itself as dominant, while ‘t’ remains hidden as recessive. This instance illustrates and indicates the law of dominance.
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