PATHOLOGY MCQ
GENETICS AND DISEASE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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1 Oval shape, thick cell wall:1 Oval shape, thin cell wall
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1 Oval shape, thick cell wall:1 Round shape, thick cell wall
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1 Round shape, thick cell wall:1 Round shape, thin cell wall
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1 Round shape, thick cell wall
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Detailed explanation-1: -In certain bacteria, an oval shape is dominant over round and thick cell walls are dominant over thin. Cross a heterozygous oval, heterozygous thick cell walled bacteria with a round, thin cell walled bacteria.
Detailed explanation-2: -Individuals carrying two identical alleles (RR or rr) are known as homozygous. While individual organisms bearing different alleles (Rr) are known as heterozygous.
Detailed explanation-3: -If the test cross results in any recessive offspring, then the parent organism is heterozygous for the allele in question. If the test cross results in only phenotypically dominant offspring, then the parent organism is homozygous dominant for the allele in question.
Detailed explanation-4: -A homozygous plant contains either of the following alleles for seed shape: (RR) or (rr). The (RR) genotype is homozygous dominant and the (rr) genotype is homozygous recessive for seed shape.