Multiple Choice QuestionsGiven below is a representation of a kind of chromosomal mutation. What is the kind of mutation represented
Deletion
Duplication
Inversion
Reciprocal translocation
C.
Inversion
During inversion a segment of chromosome gets inverted in the process of reattachment. Thus a chromosome having the genes A B C D E F G H I in linear order may get the segment DEF inverted. The new arrangement will be A B C F E D G H I. It is a chromosome aberration entailing two breaks in a chromosome followed by a reversal of the segment and consequently ofthe gene sequence in the segment. Pericentric inversion includes the centromere in the inverted segment, whereas paracentric inversions do not.
How many different types of gametes can be formed by F1 progeny, resulting from the following cross
AA BB CC x aa bb cc
3
8
27
64
Assertion : In humans, the gamete contributed by the male determines whether the child produced will be male or female.
Reason : Sex in humans is a polygenic trait depending upon a cumulative effect of some genes on X chromosome and some on Y-chromosome.
If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion
If Assertion is true but Reason is false
If both Assertion and Reason are false
One of the genes present exclusively on the X-chromosome in humans is concerned with
baldness
red-green colour blindness
facial hair/moustaches in males
night blindness
Mirabilis jalapa is an example of
complete dominance
supplementary gene
incomplete dominance
complementary gene
Which of the following is dominant character according to Mendel ?
Dwarf plant and yellow fruit
Terminal fruit and wrinkled seed
White testa and yellow pericarp
Green coloured fruit and rounded seed
Lack of independent assortment of genes A and B in fruit fly Drosophila is due to :
repulsion
linkage
crossing-over
recombination
When two mutations are located in the same functional unit or in different functional units, then it is confirmed by :
test cross
back cross
reciprocal cross
complementation test
9: 3: 3: 1 ratio is modified to 9 : 7 ratio due to
complementary gene
epistatic gene
hypostatic gene
supplementary gene
The map distance between the genes A and B is 3 units, between B and C is 10 units and between C and A is 7 units. The order of the genes in a linkage map constructed on the above data would perhaps be
A, B, C
A, C, B
B, C, A
B, A, C
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