- Trisomy and monosomy is represented respectively
by
(a) 2 n – 1 and 2n + 1
(b) 2 n + 1 and 2n – 1
(c) 2 n and 2n + 1
(d) 2 n and 2n – 1. - Given below is a representation of a kind of
chromosomal mutation. What is the kind of mutation
represented?
(a) Deletion
(b) Duplication
(c) Inversion
(d) Reciprocal translocation.- Which one of the following options (a – d) of the
number of chromosomes correctly represents the
present day hexaploid wheat?
Monosomic Haploid Nullisomic Trisomic
(a) 21 28 42 43
(b) 7 28 40 42
(c) 21 7 42 43
(d) 41 21 40 43- Male XX and female XY sometimes occur due to
(a) deletion
(b) transfer of segments in X and Y chromosome
(c) aneuploidy
(d) hormonal imbalance. - Tetraploid female of Oryza sativa is crossed with
diploid male. The ploidy levels of the embryo and
endosperm are respectively
(a) triploid and pentaploid
(b) pentaploid and triploid
(c) triploid and hexaploid
(d) hexaploid and triploid. - A pregnant woman, who has done amniocentesis test,
finds an extra Barr body in her embryo. The syndrome
which is likely to be associated with embryo is
(a) Edward’s syndrome
(b) Down’s syndrome
(c) Klinefelter’s syndrome
(d) Patau’s syndrome.
15. In crop improvement programme, haploids are of great
importance because they
(a) are useful in studies of meiosis
(b) grow better under adverse conditions
(c) give homozygous lines following diploidization
(d) require only about half of the amount of chemical
fertilizers as compared to diploids.
16. Which of the following is correct?
(a) Tetraploid plants may have wider and extensive
distribution.
(b) Aneuploidy occurs due to chromosome doubling.
(c) Notched wing margin in Drosophila is due to
duplication of B gene located on X chromosome.
(d) Raphanobrassica is an autopolyploid.
Answer Key
- (b) 2. (b) 3. (d) 4. (c)
- (a) 6. (c) 7. (a) 8. (b)
- (b) 10. (c) 11. (d) 12. (b)
- (a) 14. (c) 15. (c) 16. (a)
nn - IgE Pg. 61
- Secondary immune response Pg. 62
- Inversion Pg. 82