15.  Raphanobrassica is a classical example of
A.aneuploidy
B.nullisomy
C.allopolyploidy
D.None of the above

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16. How does dosage compensation in Drosophila occur?
A.Hypertranscription of male X chromosome
B.Hypotranscription of female X chromosome
C.X inactivation in females
D.Chimerism

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17. Hairy wing character of Drosophila is due to
A.duplication in region of chromosome
B.deletion in region of chromosome
C.due to presence of additional X-chromosome
D.due to a point mutation

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18. A diagram depicting chromosomes of haploid set of an organism ordered in a series of decreasing size is known as
A.zymogram
B.chromogram
C.idiogram
D.karyogram

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19. A cross shaped (+) or a ring involving four chromosomes may be formed during metaphase I in case of
A.translocation heterozygote
B.deficiency
C.haploid organism
D.duplication

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20. Incase of inversion when the inverted segment of chromosome includes centromere, it is known as
A.paracentric inversion
B.double inversion
C.inverted inversion
D.pericentric inversion

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21. Exchange of segments between non homologous chromosomes is best known as
A.translation
B.translocation
C.recombination
D.crossing over

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