Position of a gene on chromosome is called
The ratio of 2 : 1 is observed in case of
Test cross in plants or in Drosophila involves crossing
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Solution
In test cross, genotype of an organism showing dominant phenotype is determined by crossing it with homozygous recessive genotype.
A person with unknown blood group under ABO system, has suffered much blood loss in an accident and needs immediate blood transfusion. His one friend who has a valid certificate of his own blood type offers blood donation without delay. What would have been the type of blood group of the donor friend?
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Solution
Type O blood group is considered the universal donor blood group. It can potentially be transfused to any patient regardless of their blood type. In emergency situation, this type of blood can be given to the patient.
Mutations can be induced with :
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Solution
Mutation can be induced by gamma radiation.
When two unrelated individuals or lines are crossed, the performance of F1 hybrid is often superior to both parents. This phenomenon is called:
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Solution
Heterosis or hybrid vigor occurs when two unrelated individuals or lines are crossed, the performance of F1 hybrid, which is often superior to both is parents.
Infectious proteins are present in:
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Solution
Infections proteins are rich in prions. Prions are made of proteins without nucleic acid. It is the causal agent of scrapie disease of sheep.
Which one of the following symbols and its representation, used in human pedigree analysis is correct?
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Solution
Pedigree analysis is a record of the occurrence of a trait in several generations of a human family. In this\ male members are shown by squares and female by circles. Sibs are represented horizontally on a line in order of birth. It helps us in giving information about genotype of an individual for trait under investigation.
Select the correct statement from the ones given below with respect to dihybrid cross.
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Solution
Linkage is the inheritance of genes of same chromosome together and capacity of these genes to retain their parental combination in subsequent generation. The strength of linkage between two genes is inversely proportional to the distance between the two. This means,two linked genes show higher frequency of recombination if the distance between them is higher and lower frequency if the distance is smaller.
Which one of the following cannot be explained on the basis of Mendel’s Law of Dominance?
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Solution
According to Mendel’s law of Dominance, out of two contrasting allelomorphic factors only one expresses it self in an individual. The factor that expresses itself is called dominant while the other which has not shown its effect in the heterozygous individual is termed as recessive. The option (c ) in the given question cannot be explained on the basis of law of dominance. It can only be explained on the basis of Mendel’s Law of independent assortment,according to which in a dihybrid cross, the two alleles of each character assort independently of the alleles of other character and separate at the time of gamete formation.