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Hello students in this video i will be answering multiple questions regarding genetics and molecular biology.
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To begin with the first question, mendel's experiment with emasculation inward, removing the anthers of 1 p plant and manually transferring pollen from another plant to the emasculated plant to create a cross.
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To demonstrate that emasculation was not the reason why the wrinkle seed shape, disappeared in f1 generation, mendel performed a control experiment where he did not emasculate the flower but he covered the anthers so that there will be no self fertilization in that particular flower.
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And he crossed that flower with pollen from another plant and the results showed that f1 generation still had only round seeds indicating that emasculation was not the reason for for the disappearance of wrinkled seed shape.
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The second question, testcross used plants that were homozygous recessive because they allowed mendel to determine the genotype of the f2 plant.
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If the f2 plant was heterozygous, then crossing it with homozygous resettive plant would yield a result of 1 -1 ratio of dominant to racive alleles.
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In the offspring.
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On the other hand, if mendel had used a homozygous dominant plant for test cross, all the offspring would have a dominant phenotype, making it impossible to determine the genotype of the f2 plant.
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Moving on to the third question, variable expressivity is a term used to describe the phenomena where a genetic trite is present in different individuals to varying degrees...