Monohybrid Cross Problem Set

Problem 7: The test cross


To identify the genotype of yellow-seeded pea plants as either homozygous dominant (YY) or heterozygous (Yy), you could do a test cross with plants of genotype _______.
A. y

B. Y

C. yy

A cross with the homozygous recessive (yy) is a test cross. If the parent of unknown genotype is heterozygous (Yy), half of the offspring will have the recessive trait. The unknown genotype could also be determined by a cross with a known heterozygote (Yy).


E. Yy

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Thursday, October 1, 1998
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