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Wake-up. Cross a heterozygous man for eyebrows with a woman with a unibrow . A unibrow is a recessive trait. What are the chances of them having a child with a unibrow ?. Special Crosses: Incomplete Dominance and Codominance. What is Incomplete Dominance?.
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Wake-up • Cross a heterozygous man for eyebrows with a woman with a unibrow. A unibrow is a recessive trait. • What are the chances of them having a child with a unibrow?
What is Incomplete Dominance? • Blending of the dominant and recessive alleles in heterozygous • 3rd phenotype
Plant: Snapdragons White: r Red: R
Humans: Hair Type Straight: c Curly: C
In snapdragons, red flowers are dominant over white flowers. The heterozygous genotype has pink flowers. Cross a homozygous red-flowered plant with a pink flowered plant. What are the chances of producing white flowers? (R = red and r = white)
If a yellow guinea pig is crossed with a white one, the offspring are cream-colored. What kinds of offspring are expected if two cream-colored guinea pig mate? (Y = yellow and y = white)
What is Codominance? • Both dominant and recessive alleles are expressed in heterozygous • 3rd phenotype
Chickens: Feather Color White: b Black: B
Cattle: Fur Color Red: R White: r
In certain cattle, hair color can be red (homozygous RR), white (homozygous rr), or roan (a mixture of red and white hairs, heterozygous Rr). When a red bull is mated to a white cow, what genotypes and phenotypes of offspring could be obtained?
If one of the offspring found above were mated to a white cow, what genotypes and phenotypes of offspring could be produced? In what proportion?