Principles and inheritance of variation: DPP-1

1. Experimental verification of the chromosomal theory of inheritance was done by

(a) Sutton
(b) Boveri
(c) Morgan
(d) Mendel
2. Embryological support for evolution was disapproved by
(a) Alfred Wallace
(b) Charles Darwin
(c) Oparin
(d) Karl Ernst von Baer
3. The production of gametes by the parents, the formation of zygotes, the F1 and F2 plants, can be
understood using
(a) Wenn diagram
(b) Pie diagram
(c) A pyramid diagram
(d) Punnet square
4. In a marriage between male with blood group A and female with blood group B, the progeny had
either blood group AB or B. What could be the possible genotype of parents?
(a) IAi (Male); IBi (Female)
(b) IAi (Male); IB IB (Female)
(c) IA IA (Male); IB IB (Female)
(d) IA IA (Male); IB i (Female)
5. In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F_{1}
generation, pink flowers were obtained. When pink flowers were selfed, the F_{2} generation
showed white, red and pink flowers. Choose the incorrect statement from the following:
(a) This experiment does not follow the principle of dominance.
(b) Pink colour in F1 is due to incomplete dominance.
(c) Ratio of F2 is ¼ (Red) ½ (Pink) ¼ (White)
(d) Law of Segregation does not apply in this experiment.
6. What map unit (Centimorgan) is adopted in the construction of genetic maps?
(a) A unit of distance between two expressed genes, representing 10% cross over.
(b) A unit of distance between two expressed genes, representing 100% cross over.
(c) A unit of distance between genes on chromosomes, representing 1% cross over.
(d) A unit of distance between genes on chromosomes, representing 50% cross over
7. Select the incorrect statement.
(a) Male fruit fly is heterogametic.
(b) In male grasshoppers, 50% of sperms have no sex-chromosome.
(c) In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
(d) Human males have one, of their sex- chromosome much shorter than the other.
8. A woman has an X-linked condition on one of her X chromosomes. This chromosome can be
inherited by
(a) Only daughters
(b) Only sons
 (c) Both sons and daughters
(d) Only grandchildren
9. Which of the following characteristics represent ‘Inheritance of blood groups’ in humans?
A. Dominance
B. Co-dominance
C. Multiple allele
D. Incomplete dominance
E. Polygenic inheritance
(a) B, C and E
(b) A, B and C
(c) B, D and E
(d) A, C and E
10. The genotypes of a husband and wife are IaIb and I ai Among the blood types of their children,
how many different genotypes and phenotypes are possible?
(a) 3 genotypes; 4 phenotypes
(b) 4 genotypes; 3 phenotypes
(c) 4 genotypes; 4 phenotype
(d) 3 genotypes; 3 phenotypes
11. Among the following characters, which one was not considered by Mendel in his experiments on
pea?
(a) Trichomes – Glandular or non-glandular
(b) Seed Green or Yellow
(c) Pod-Inflated or Constricted
(d) Stem-Tall or Dwarf
12. Which one from those given below is the period for Mendel’s hybridisation experiments?
(a) 1840-1850
(b) 1857-1869
(c) 1870-1877
(d) 1856-1863
13. A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant.
When the F₁ plants were selfed the resulting genotypes were in the ratio of
(a) 1:2:1:: Tall homozygous: Tall heterozygous: Dwarf
(b) 1:2:1:: Tall heterozygous: Tall homozygous: Dwarf
(c) 3:1:: Tall: Dwarf
(d) 3:1:: Dwarf: Tall
14. In order to find out the different types of gametes produced by a pea plant having the genotype
AaBb, it should be crossed to a plant with the genotype:
(a) AABB
(b) AaBb
(c) aabb
(d) aaBB
15. In a test cross involving F₁ dihybrid flies, more parental type offspring were produced than the
recombinant type offspring. This indicates
(a) The two genes are located on two different chromosome
 (b) Chromosomes failed to separate during meiosis.
(c) the two genes are linked and present on the same chromosome.
(d) Both of the characters are controlled by more than one gene.
16. A cell at telophase stage is observed by a student in a plant brought from the field. He tells his
teacher that this cell is not like other cells at telophase stage. There is no formation of cell plate
and thus the cell is containing more number of chromosomes as compared to other dividing
cells. This would result in
(a) Aneuploidy
(b) Polyploidy
(c) Somaclonal variation
(d) Polyteny
17. How many pairs of contrasting characters in pea plants were studied by Mendel in his
experiments?
(a) Six
(b) Eight
(c) Seven
(d) Five
18. Which is the most common mechanism of genetic variation in the population of sexually
reproducing organism?
(a) Chromosomal aberrations
(b) Genetic drift
(c) Recombination
(d) Transduction
19. Alleles are
(a) True breeding homozygotes
(b) Different molecular forms of a gene
(c) heterozygotes
(d) Different phenotype
20. In his classic experiments on Pea plants, Mendel did not use
(a) Pod length
(b) Seed shape
(c) Flower position
(d) Seed colour
21. A man with blood group ‘A’ marries a woman with blood group ‘B’. What are all the possible
blood groups of their offsprings?
(a) A,B and AB only
(b) A,B,AB and O
(c) O only
(d) A and B only
22. Multiple alleles are present :
(a) At different loci on the same chromosome
(b) At the same locus of the chromosome
(c) On non-sister chromatids
(d) On different chromosomes
23. A gene showing codominance has:
(a) Alleles tightly linked on the same chromosome
(b) Alleles that are recessive to each other
(c) both alleles independently expressed in the heterozygote
(d) One allele dominant on the other
24. The term ‘linkage’ was coined by:
(a) T. Boveri
(b) G. Mendel
(c) W. Sutton
(d) T.H. Morgan
25. Fruit colour in squash in an example of :
(a) Recessive epistasis
(b) Dominant epistasis
(c) Complementary genes
(d) Inhibitory genes
26. In a population of 1000 individuals 360 belong to genotype AA, 480 to Aa and the remaining 160
to aa. Based on this data, the frequency of allele A in the population is:
(a) 0.4
(b) 0.5
(c) 0.6
(d) 0.7
27. If two persons with ‘AB’ blood group marry 3 and have sufficiently large number of children
these children could be classified as ‘A’ blood group: ‘AB’ blood group: ‘B’ blood group in 1:2:1
ratio. Modern technique of protein electrophoresis reveals presence of both ‘A’ and ‘B’ type
proteins in ‘AB’ blood group individuals. This is an example of:
(a) Incomplete dominance
(b) Partial dominance
(c) Complete codominance
(d) Codominance
28. Which Mendelian idea is depicted by a cross in which the F₁ generation resembles both the
parents?
(a) Law of dominance
(b) Inheritance of one gene
(c) Co-dominance
(d) Incomplete dominance
29. Which of the following statements is not true of two genes that show 50% recombination
frequency?
(a) The genes are tightly linked
(b) The genes show independent assortment
(c) If the genes are present on the same chromosome, they undergo more than one
crossovers in every meiosis
(d) The genes may be on different chromosomes
30. Genetic variation in a population arises due to :
(a) Mutations only
 (b) Recombination only
(c) Mutations as well as recombination
(d) Reproductive isolation and selection
31. A certain road accident patient with unknown blood group needs immediate blood transfusion.
His one doctor friend at once offers his blood. What was the blood group of the donor?
(a) Blood group B
(b) Blood group AB
(c) Blood group O
(d) Blood group A
32. A test cross is carried out to
(a) Determine the genotype of a plant at F2.
(b) Predict whether two traits are linked.
(c) assess the number of alleles of a gene.
(d) Determine whether two species or varieties will breed successfully.
33. F, generation in a Mendelian cross showed that both genotypic and phenotypic ratios are same
as 1: 2: 1. It represents a case of:
(a) Co-dominance
(b) Dihybrid cross
(c) Monohybrid cross with complete dominance
(d) Monohybrid cross with incomplete dominance
34. When two unrelated individuals or lines are crossed, the performance of F₁ hybrid is often
superior to both parents. This phenomenon is called:
(a) Heterosis
(b) Transformation
(c) splicing
(d) Metamorphosis
35. 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?
(a) Type B
(b) Type AB
(c) Type O
(d) Type A
36. Test cross in plants or in Drosophila involves crossing
(a) Between two genotypes with recessive trait
(b) Between two F₁ hybrids
(c) the F₁ hybrid with a double recessive genotype.
(d) Between two genotypes with dominant trait
37. Which one of the following conditions of the zygotic cell would lead to the birth of a normal
human female child?
(a) Two X chromosomes
(b) Only one Y chromosome
(c) Only one X chromosome
 (d) One X and one Y chromosome
38. Which one of the following cannot be explained on the basis of Mendel’s Law of Dominance?
(a) The discrete unit controlling a particular character is called a factor
(b) Out of one pair of factors one is dominant, and the other recessive
(c) Alleles do not show any blending and both the characters recover as such in F2
generation.
(d) Factors occur in pairs
39. The genotype of a plant showing the dominant phenotype can be determined by:
(a) Test cross
(b) Dihybrid cross
(c) pedigree analysis
(d) Back cross
40. Select the correct statement from the ones given below with respect to dihybrid cross.
(a) Tightly linked genes on the same chromosome show higher recombinations
(b) Genes far apart on the same chromosome show very few recombinations
(c) Genes loosely linked on the same chromosome show similar recombinations as the
tightly linked ones
(d) Tightly linked genes on the same chromosome show very recombinations few
41. A common test to find the genotype of a hybrid is by :
(a) Crossing of one F2progeny with female parent
(b) Studying the sexual behaviour of F1 progenies
(c) crossing of one F1 progeny with male parent
(d) Crossing of one F2 progeny with male parent.
42. Two genes R and Y are located very close on the chromosomal linkage map of maize plant. When
RRYY and rryy genotypes are hybridized, the F2 segregation will show
(a) Segregation in the expected 9:3:3:1 ratio
(b) Segregation in 3: 1 ratio
(c) higher number of the parental types
(d) Higher number of the recombinant types.
43. In pea plants, yellow seeds are dominant to green. If a heterozygous yellow seeded plant is
crossed with a green seeded plant, what ratio of yellow and green seeded plants would you
expect in F1 generation?
(a) 9:1
(b) 1:3
(c) 3:1
(d) 50:50
44. Inheritances of skin colour in humans is an example of
(a) Point mutation
(b) Polygenic inheritance
(c) codominance
(d) Chromosomal aberration.
45. A human male produces sperms with the genotypes AB, Ab, aB, and ab pertaining to two
diallelic characters in equal proportions. What is the corresponding genotype of this person?
(a) AaBB
 (b) AABb
(c) AABB
(d) AaBb
46. Which one of the following is an example of polygenic inheritance?
(a) Production of male honey bee
(b) Pod shape in garden pea
(c) Skin colour in humans
(d) Flower colour in Mirabilis jalapa
47. In Mendel’s experiment with garden pea, round seed shape (RR) was dominant over wrinkled
seeds (rr), yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the
expected phenotypes in the F₂ generation of the cross RRYY × rryу?
(a) Only wrinkled seeds with yellow cotyledons
(b) Only wrinkled seeds with green cotyledons
(c) Round seeds with yellow cotyledons, and wrinkled seeds with yellow cotyledons
(d) Only round seeds with green cotyledons
48. Test cross involves:
(a) Crossing between two F1 hybrids
(b) Crossing the F₁ hybrid with a double recessive genotype
(c) crossing between two genotypes with dominant trait
(d) Crossing between two genotypes with recessive trait
49. Phenotype of an organism is the result of
(a) Cytoplasmic effects and nutrition
(b) Environmental changes and sexual dimorphism
(c) genotype and environment interactions
(d) Mutations and linkages
50. How many different kinds of gametes will be produced by a plant having the genotype AABbCC?
(a) Four
(b) Nine
(c) Two
(d) Three

Answer key

1. C
2. D
3. D
4. B
5. D
6. C
7. C
8. C
9. B
10. D
11. A
12. D
13. A
14. C
15. C
16. B
17. C
18. C
19. B
20. A
21. B
22. B
23. C
24. D
25. B
26. C
27. D
28. C
29. A
30. C
31. C
32. A
33. D
34. A
35. C
36. C
37. A
38. C
39. A
40. D
41. C
42. C
43. D
44. B
45. D
46. C
47. C
48. B
49. C
50. C