GENETICS AND EVOLUTION
MOLECULAR BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1:1
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2:1
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3:1
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4:1
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Detailed explanation-1: -A testcross to a heterozygous individual should always yield about a 1:1 ratio of the dominant to recessive phenotype.
Detailed explanation-2: -Tutorial. The expected genotype ratio when two heterozygotes are crossed is 1 (homozygous dominant) : 2 (heterozygous) : 1 (homozygous recessive).
Detailed explanation-3: -The dominant trait is expressed in the phenotype and suppresses the recessive trait.
Detailed explanation-4: -That is, when crossed among themselves, they yield only homozygous recessive individuals. A monohybrid cross results in a phenotypic ratio of 3:1 (dominant to recessive), and a genotypic ratio of 1:2:1 (homozygous dominant to heterozygous to homozygous recessive).
Detailed explanation-5: -What is a 1:1 phenotypic ratio? A 1:1 phenotypic ratio occurs when there are only two phenotype possibilities as outcomes when organisms are crossed and they both have a 50/50 chance of appearing.