PATHOLOGY MCQ
GENETICS AND DISEASE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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one trait is crossed.
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two traits are crossed.
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four boxes are needed for the punnett square.
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mom’s alleles are dominant.
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Detailed explanation-1: -A dihybrid cross is a breeding experiment between two organisms which are identical hybrids for two traits. In other words, a dihybrid cross is a cross between two organisms, with both being heterozygous for two different traits. The individuals in this type of trait are homozygous for a specific trait.
Detailed explanation-2: -A dihybrid cross allows us to look at the pattern of inheritance of two different traits at the same time. For example, say we are crossing two pea plants. The two traits we are looking at are the seed color and shape. The first seed is green and wrinkly, and the second is yellow and round.
Detailed explanation-3: -A dihybrid cross-examines the inheritance of two traits at the same time. Dihybrid crosses are more complicated than monohybrid crosses. With unlinked genes, a 9:3:3:1 phenotypic ratio will result in the offspring of a cross of two completely heterozygous individuals.
Detailed explanation-4: -A dihybrid is an individual who is heterozygous for two genes. These individuals have a dominant and a recessive allele for each of the genes. Because dominant alleles are always expressed in mendelian genetics, a dihybrid individual will have the dominant phenotype for both characteristics the genes code for.