Monohybrid Cross Problem Set

Problem 1: The monohybrid cross

In pea plants, spherical seeds (S) are dominant to dented seeds (s). In a genetic cross of two plants that are heterozygous for the seed shape trait, what fraction of the offspring should have spherical seeds?
A. None

B. 1/4

C. 1/2

D. 3/4

3/4 of the offspring will have the dominant phenotype: one fourth will be homozygous dominant (SS) and one half will be heterozygous (Ss.)
One fourth will be homozygous recessive (ss) and will have the recessive phenotype.

E. All

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