Principles Of Inheritance And Variation Questions

We provide principles of inheritance and variation practice exercises, instructions, and a learning material that allows learners to study outside of the classroom. We focus on principles of inheritance and variation skills mastery so, below you will get all questions that are also asking in the competition exam beside that classroom.

List of principles of inheritance and variation Questions

Question No Questions Class
1 How is the arrangement of Mendel’s
selected seven characters on four
chromosomes?
A. One in chromosome no. 1,4 in chromosome no. ( 4, ) one in chromosome no. 5 , and one in chromosome no. 7
B. 2 in chromosome no. 1 , 3 in chromosome no. 4 , one in chromosome no. 5 and one in chromosome no. 6
C. 3 in chromosome no. 1,1 in chromosome no. 4,2 in chromosome no. 5 and one in chromosome no. 7
D. 2 in chromosome no. 1,3 in chromosome no. 4,1 in
chromosome no. 5 and 1 in chromosome no. 7
12
2 How many X chromosomes are present in a male?
( mathbf{A} cdot mathbf{0} )
B.
( c cdot 2 )
( D )
12
3 How is co-dominance different from
incomplete dominance and dominance?
12
4 The human offspring can be of two types with ( mathrm{XX} ) and ( ldots ldots . . . ) chromosomes.
A. ( x y )
B. xxx
( c cdot x x x )
D. YY
12
5 The transmission of traits from parents to offspring is called
A. Characteristic
B. Heredity
c. Donation
D. Both A and B
12
6 Pea plants were more suitable than cattle for Mendel’s experiment because
A. There were no breeding records of cattles
B. Pea plants can be self-fertilised
c. cattle are not easy to mantain
D. All pea plants have 2n chromosomes and fewer genetic traits.
12
7 Branch of biology dealing with heredity and variations is
A. Ecology
B. Evolution
c. Palaeontology
D. Genetics
12
8 In humans, sex is determined by
A. Y-chromosome
B. X-chromosome
c. A and X-chromosome
D. A and Y-chromosome
12
9 The sex of every animal depends on the fusion.
A. Chromosomal
B. Bloodd
c. RNA
D. None of these
12
10 Name of the following:
Appearance of a trait due to the presence of an allele exclusively on
either the ( X ) chromosome or on the ( Y )
chromosome.
12
11 Mendel selected Pea as material for his
experiments because
A. It is an annual plant with comparatively short life cycle
B. The flowers are self-pollinated
c. The number of seeds produced is quite large
D. All the above
12
12 Structure present in a cell which is responsible for determination of the sex of a baby is
A . Cytoplasm
B. Cell membrane
c. Nucleus
D. chromosome
12
13 A husband and wife have normal vision
but fathers of both of them were colour
blind. Probability of their first daughter to be colour blind is
A . 25%
B. 50%
c. 75%
D. 0%
12
14 Define Heredity. Give two examples. 12
15 How is sex determination happen in
birds and honeybees?
12
16 Briefly explain the following terms:
(i) monohybrid cross
( (i i) )
Biomedical waste
(iii) Innate
immunity.
(iv) Diapedesis
(v) Hormones.
12
17 Which one of the following scientist’s name is correctly matched with the theory put forth by him?
A. De Vries – Theory of natural selection
B. Darwin – Theory of pangenesis
c. Weismann – Theory of continuity of germplasm
D. Pasteur – Theory of inheritance of acquired characters
12
18 Three Mark Questions How has sex originated? 12
19 Will it be possible to judge the sex of the child by them? 12
20 The principle of independent
assortment means
A. Separation of characters of one parent
B. Non-Separation of characters of one parent
C. Separation of characters of both parents together
D. Combination of both parental characters
12
21 A woman has only daughters, analyse the situation genetically and provide a suitable explanation. 12
22 Both chromosome and gene (Mendelian factors) whether dominant or recessive
are transmitted from generation to generation in which form
A. changed
B. unaltered form
c. altered form
D. disintegrated
12
23 Mendel was born in
A. 17th century
B. 18th century
c. 19th century
D. 8th century.
12
24 Test cross can not be performed in
A. Neurospora
B. Man
c. Pea
D. Dog
12
25 Which one of the following traits of Garden Pea studied by Mendel was a recessive feature?
A. Axial flower position
B. Green seed colour
c. Green pod colour
D. Round seed shape
12
26 In honey bee the drones (males) are
produced from
A. Unfertilized eggs
B. Fertilized eggs
C. Larvae from unfertilized eggs, which are fed on royal jelly
D. Larvae from unfertilized eggs, which are not cared by the workers at all
12
27 What is the blending theory of
inheritance?
A. Mendels theory of how the traits of parents are passed to offspring through the gametes
B. Darwins theory of how traits are passed from all parts of the parents body into the gamete to be transmitted to the offspring
C. The modern theory of how genetic information is passed from parents to offspring
D. An old theory that said that offspring show traits intermediate between those of the parents
12
28 A trait in an organism is influenced by
A. Paternal DNA only
B. Maternal DNA only
C. Both maternal and paternal DNA
D. Neither by paternal nor by maternal DNA
12
29 Male heterogametic sex, ( X X, X O ) type of sex determination is found in
A. Butterflies
B. Moths
c. Grasshoppers
D. Drosophila
12
30 Mendal carried out his investigations on which plant?
A. Peanuts
B. Pigeon Pea
c. Garden Pea
D. Gram
12
31 Assertion
In humans, the gamete contributed by the male determines whether the child
produced will be male or female.
Reason
Sex in humans in a polygenic trait
depending upon a cumulative effect of
some genes on ( X ) chromosome and
some on Y chromosome.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect.
D. Both Assertion and Reason are incorrect.
12
32 Mating of an organism to double recessive for determining homozygosity or heterozygosity is called as
A. Reciprocal cross
B. Back cross
c. Dihybrid cross
D. Test cross
12
33 Explain the mechanism of sexdetermination in humans. 12
34 Independent assortment is absent in
case of
A. Genes located on the same chromosome
B. Genes located on homologous chromosomes
c. Genes located on nonhomologous chromosomes
D. All of the above
12
35 Who is know as father of Genetics? 12
36 Probability of four son to a couple is
A ( cdot frac{1}{4} )
в. ( frac{1}{8} )
c. ( frac{1}{16} )
D. ( frac{1}{32} )
12
37 “Like begets like” an important and universal phenomenon of life is due to
A. Eugenics
B. Inheritance
c. Dominance
D. crossing-over
12
38 93. Arrangement in order of occur-
rence
(1) timely (2) chronological
(3) chronic (4) temporal
12
39 When two individual of ( mathrm{F} 1 )
generation are crossed with each other the phenomenon is called
A. Test cross
B. Back cross
c. Self cross
D. None of the above
12
40 Which of the following condition occurs
in the person with genotype ( X 0 ? )
A. Cannot survive.
B. Will have immature, ambiguous (both male and female) reproductive systems.
C. Will be phenotypically female but sterile
D. Does not produce steroid hormones.
E. None of the above
12
41 What is parental generation(p)? 12
42 Among seven pairs of traits studied by Mendel, the number of traits related to
flower, pod and seed were
A ( . ) 2, 2, 2
B. 2, 2, 1
( c cdot 1,2,2 )
D. 1,1,2
12
43 Study this figure and answer the
question. What would B and C
represent?
A. Zonly
B. Wonly
( c . z ) and ( w )
( D . ) ww
12
44 With the help of suitable examples, explain why certain traits cannot
be passed on to the next generation. What are such traits called?
12
45 The determination of sex of the child
depends on the chromosome of
A. Female
в. Male
c. The child itself
D. None of the above
12
46 Peacock shows which of the following
genotype?
A. ( x x )
B. XY
( c cdot z z )
D. zw
12
47 Male ( X X ) and female ( X Y ) sometime such
conditions occur due to
A. Deletion
B. Transfer of segments in ( x ) and ( Y ) chromosomes
c. Aneuploidy
D. Hormonal imbalance
12
48 In bugs and cockroaches (insects), the sex determinations takes place by
A. ( x x ) and ( x o ) chromosomes
B. ( x x ) and ( x ) y chromosomes
c. zz – zw chromosomes
D. zo – zz chromosomes
12
49 The inheritance of sex chromosomes in
human can be described by the fact that:
A. The gametes from each parent have either an ( x ) or a ( Y ) chromosome.
B. The gamete from the mother has either an ( x ) or ( Y ) chromosomes
c. The gamete from the father has either an ( x ) or a chromosome.
D. The gamete from the father only has an ( x ) chromosome.
E. The gamete from the mother has only a ( Y ) chromosome
12
50 DNA in the offsprings is contributed by
A. Male parent
B. Female parent
C. Both male and female parent equally
D. None of the above
12
51 41. Thalassemia is an example of
(1) Deletion mutation
(2) Point mutation
(3) Silent mutation
(4) Frame shift mutation
12
52 Reduction in weight of an organism due to nutrition is genetically controlled.
A. True
B. False
12
53 Assume that blue flowered plant is dominant character over the white.
When a blue flowered plant is crossed
with its white flowered plant, the
progeny showed ( 50 % ) of plants with blue flowers is with white flowers. The
genotypes of blue and white parents respectively are
( A cdot b b, b b )
B. ВВ, Вь
( c cdot B B, b b )
D. Bb, bb
12
54 Define trait 12
55 Which one of the following conditions of the zygotic cell will produce a normal human female child?
A. Only heterologous X chromosome
B. One ( x ) and one ( Y ) chromosome
c. Two homologous ( x ) chromosome
D. Only one Y chromosome
12
56 Assertion
XX-XY type of sex determination mechanism is an example of female heterogamety and is found in
Drosophila.
Reason
Male heterogamety is seen in moths
where males produce two different
types of gamete.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
57 What is the technique for in vitro sex determination? 12
58 The genotype of offspring formed from Tt ( x ) tt will be
A. ( pi ) and tt
B. Tt and tt
c. only tt
D. only TT
12
59 Identify the wrong statement
A. In male grasshoppers, ( 50 % ) of the sperms have no sex chromosome.
B. Usually female birds produce two types of gametes based on sex chromosomes.
c. The human males have one of their sex chromosomes much shorter than the other.
D. The male fruit fly is heterogametic.
E. In domesticated fowls, the sex of the progeny depends on the type of sperm that fertilizes the egg.
12
60 Does the sex of the child depend on the father or it is just a matter of chance?
Discuss.
12
61 Bird females have chromosome
arrangement as
A. ( x y )
B. xo
( c cdot w z )
D. ww
12
62 How many X chromosomes are present in a female?
( mathbf{A} cdot mathbf{0} )
B.
( c cdot 2 )
( D )
12
63 Which one is not a dominant trait
amongst seven Pea traits chosen by
Mendel?
A. Flower Colour – Purple
B. Pod Colour – Yellow
c. Shape of Seed – Round
D. Flower – Axial.
12
64 Which of the two, sperm or egg cell (ovum), decides the sex of the child? 12
65 Which of the following is true for the inheritance of sex chromosomes in
humans?
A. The gametes from each parent have either an ( x ) or a chromosome.
B. The gamete from the mother has either an ( x ) or a ( y ) chromosome.
c. The gamete from the father has either an ( x ) or a chromosome.
D. The gamete from the father only has an ( x ) chromosome.
E. The gamete from the mother only has a ( Y ) chromosome.
12
66 Three Mark Questions:
Women are often blamed for producing female children. Consequently they are ill treated and ostracized. How will you address this issue scientifically it you
were to conduct an awareness
programme to highlight the values
involved?
12
67 How did Mendel explain that it is
possible that a trait is inherited but not expressed in an organism?
12
68 In Drosophila sex is determined by
A. ( x ) and ( Y ) chromosomes
B. Ratio of pairs of X-chromosomes to the pairs of autosomes
C. Ratio of number of X-chromosomes to the sets of
autosomes
D. Whether the egg is fertilized or develops parthengenetically
12
69 What proportion of the ( f ), generation will be short will wrinkled seeds when
pure tall round plant is crossed with pure dwarf wrinkled seeded plant?
A. None
B. 25%
c. ( 50 % )
D. ( 75 % )
12
70 How many of the structures (A to D) in
the following diagram are diploid?
( mathbf{A} )
( B )
( c )
( D )
12
71 Lyon hypothesis deals with
A. Centromere position
B. Genetic compatibility
c. Genetic incompatibility
D. Number of Barr bodies
12
72 In chickens, the female is the homogametic sex.
A. True
B. False
12
73 Select the incorrect statement.
A. Male fruit fly is heterogametic
B. In male grasshoppers ( 50 % ) of sperms have no sexchromosome
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
12
74 Male heterogametic, XX-XO type of sex determination is found in
A. Butterflies
B. Moth
c. Grasshoppers
D. Drosophila
12
75 In human zygote male sex is determined by
A. Strength of father
B. Nutrition of mother
c. composition of required chromosome pair
D. None of the above
12
76 A Drosophila has ( X X X Y Y ) sex chromosomes. All the autosomal
chromosomes are normal. The sexual
phenotype will be.
A. Normal female
B. Super female
c. Intersexual
D. Male
12
77 A zygote which has an ( X ) chromosome inherited from the father will become
A. Boy
B. Girl
C. Either girl or boy
D. cannot be predicted
12
78 How do mendel’s experiments show
that
(a)traits may be dominant or recessive?
(b) inheritance of two traits is
independent of each other
12
79 What will happen, if the sperm
containing ‘ ( X^{prime} ) chromosomes fertilises
the Ovum?
A. Female child born
B. Male child born
c. can not guess
D. None
12
80 33. Coupling and repulsion are the
two states of :
(1) linkage
(2) chiasma
(3) mutation (4) crossing over
12
81 Explain the sex determination in human beings. 12
82 Sex chromosomes of a female bird are
A. xo
B. zz
c. zw
D. xx
E. ( x y )
12
83 Which of the following possess homogametic male?
A. Plant
B. Man
c. Insect
D. Birds
12
84 The maleness of a child is determined
by
A. The ( x ) chromosome in the zygote
B. The Y chromosome in zygote
C. The cytoplasm of germ cell which determines the sex
D. Sex is determined by chance
12
85 Drosophila with ( 2 A+X O ) are
A. Fertile female
B. Infertile female
c. sterile male
D. Intersexes
12
86 When a cross is made between a tall
plant with yellow seeds (Tt Yy) and a tall plant with green seeds (Tt yy), what is true regarding the proportions of phenotypes of the offsprings in ( F 1 ) generation? Proportion of Tall and Green Proportion of Dwarf and Green
A ( cdot frac{3}{8} frac{1}{8} )
в. ( frac{2}{8} frac{1}{8} )
c. ( frac{1}{8} frac{3}{8} )
D. ( frac{2}{8} frac{2}{8} )
12
87 Explain the mechanism of ‘sex
determination’ in birds. How does it
differ from that of human beings?
12
88 Mendel was lucky in the choice of the material of his experiments, which of the following contributed to his success?
A. He observed distinct inherited traits
B. He qualitatively analysed his date.
c. He liked pea plants
D. He considered only one character at one time.
12
89 A child who inherits an Y chromosome
from father will be a girl.
A. True
B. False
12
90 In which type of inheritance the results are affected by reciprocal cross?
A. Nuclear
c. Blending
D. All of the above
12
91 Most favourite and ideal material for
researches in genetics is
A. Housefly
B. Mosquito
c. Frog
D. Fruitfly
12
92 In what the study of ( X X-X O ) type method was done initially?
A. Drosophila
B. Butterfly
c. Grass hopper
D. squash – bug
12
93 Word genetics comes from
A. Gene
B. Genesis
C. Genome
D. Genomics
12
94 Which is correct?
( A ). Birds have ( Z Z ) -ZW sex determination
B. Diosophilla has ( X X ) -XY sex determination
C. Henking discovered Y-ch
D. Grasshoppers show X-XY sex determination
12
95 Which of the following is dominant trait in pea?
A. Wrinkled seed
B. White flower
c. Dwarf plant
D. Green podd
12
96 With the help of an example justify the following statement: “A trait may be inherited, but may not be expressed”. 12
97 The figure shows sex determination in
humans.

What are the right substitutes for the
numbers 1 to 6?

12
98 Given the pair of contrasting traits of the following characters in pea plant and mention if it’s dominant or
recessive.
Round seed
A. Dominant
B. Recessive
c. Incomplete dominant
D. None of these
12
99 The total number of chromosomes in an
organism with haploid number of 18 would be
( A cdot 18 )
B. 16
( c cdot 26 )
D. 36
E. 46
12
100 f a heterozygous tall pea plant is selfpollinated, what will be the heterozygous: homozygous proportion of the progenies?
A . 1: 3
B. 1:
( c .3: )
D. 1: 2
12
101 Mendel choose pea plant due to
A. Its economic importance
B. Presence of contrasting characters
C . Its availability
D. Its cheapness
12
102 Male and female birds have the
following set of chromosomes.
A. zz and zw
B. ( x x ) and ( x 0 )
c. zz and zo
D. ( x ) y and ( x x )
12
103 Write a note on the following:
(i) Genetic Code
(ii) Sex – determination in human.
12
104 In our society, women are blamed for
producing female children. Choose the correct option for sex determination in
humans.
A. Due to some defect like aspermia in man
B. Due to genetic makeup of some particular sperm which fertilizes the eggg
c. Due to genetic makeup of the eggs
D. Due to some defect in women
12
105 Mendel was born in
A. Australia
B. Heizendorf
C . Maravia
D. Brunn
12
106 How chromosomes determine sex of a
baby?
12
107 Sex of the child is determined by the type of ( ldots ) provided by the father.
A. Sperm
B. Ovum
c. Embryo
D. Placenta
12
108 Which one of the following traits of garden pea studied by Mendel was a recessive feature?
A. Green seed colour
B. Green pod colour
c. Round seed shape
D. Axial flower position
12
109 In humans, the composition of a zygote that will develop into a female is
( mathbf{A} cdot 44 A+X X )
B. ( 44 A+X Y )
( c cdot 22+X )
D. ( 23 A )
12
110 Describe the steps of procedure of
Mendel’s experiments with suitable example.
12
111 Is the sperm or the egg responsible for the sex of the chicks? 12
112 Assertion
In humans the gamete contributed by the male determines whether the child
produced will be male or female.
Reason

Sex in humans is polygenic trait
dependent upon the cumulative effect
of some genes on X-chromosome and
some on Y-chromosome.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect.
D. Both Assertion and Reason are incorrect.

12
113 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.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect

12
114 A true breeding plant producing red flowers is crossed with a pure plant producing white flowers. Allele for red colour of flower is dominant. After
selfing the plants of first filial generation, the proportion of plants producing white flowers in the progeny would be
( A cdot frac{3}{4} )
B.
( c cdot frac{1}{3} )
( D )
12
115 Assertion
In pigeons, females are heterogametic and males are homogametic.
Reason
In pigeons, females have ( z ) W sex chromosomes and males have ( mathrm{ZZ} ) sex
chromosomes.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
c. Assertion is correct but Reason is incorrect
D. Both Assertion and Reason are incorrect
12
116 Sex chromosomes of birds are
B. zz-ww
c. ( x x-x y )
D. xo-xxx
12
117 Which one of the following conditions correctly describes the manner of determining the sex in the given example?
A. Homozygous sex chromosomes (ZZ) determine female sex in birds
B. X0 type of sex chromosomes determine male sex in grasshopper.
c. xo condition in human as found in Turner syndrome determines female sex
D. Homozygous sex chromosomes (XX) produce male in Drosophila
12
118 Choose the correct answer from the
alternatives given.
A couple has six daughters, What is the possibility of their having a girl next time?
A . 10%
B. 50%
c. ( 90 % )
D. 100%
12
119 Describe chromosomal theory of sex determination 12
120 Which plant did mendel select for his experiments ? Why? Explain any three charateristics the same. 12
121 Read the following statements and find out the incorrect statement.
A) Genetics deals with the inheritance
as well as variation of characters from
parents to offspring
B) Variation is the process by which characters are passed on from parent to
progeny
C) Inheritance is the basis of heredity
D) Inheritance is the degree by which
progeny differ from their parents
E) Human knew from as early as
( 8000-10000 B . C . ) that one of the
causes of variation was hidden in
sexual reproduction
( A cdot B, D ) and ( E ) only
B. A, C and E only
C. B and D only
D. E only
12
122 Which is not an example of cytoplasmic inheritance?
A. Female sterility in maize
B. Sigma particle inheritance
c. Kappa particle inheritance
D. Plastid inheritance
12
123 How many pairs of contrasting characters in pea were chosen by
Mendel?
A . 3
B. 5
( c cdot 7 )
D.
12
124 A woman has only daughters. Which of the following is the suitable explanation
for it?
A. The man produces sperms with ( x ) and ( Y ) chromosome but only that with ( Y ) chromosomes are viable
B. The man produces sperms with ( x ) and ( Y ) chromosome but only that with ( x ) chromosomes are viable
c. The man produces sperms with ( x ) and ( Y ) chromosome and all are viable
D. None of the above
12
125 Which one carries extra nuclear genetic material?
A. Plastid
B. Ribosomes
c. chromosomes
D. Golgi complex
12
126 A son inherits an ( X ) chromosome from
A. Mother
B. Father
c. Both A and B
D. Grandparents
12
127 What is meant by
In honey bee, males don’t have fathers
& thus can’t have sons…but have a
grand father ( & ) can have grand sons…??
12
128 Five Mark Questions:
(a) Explain the mechanism of sex determination in humans.
(b) Differentiate between male heterogamety and female heterogamety with the help of an example of each
12
129 Which technique is used by Mendel for hybridisation?
A. Emasculation
B. Bagging
c. Meristem culture
D. Both A and B
12
130 Mohan has two daughters. He blames his wife for bearing only daughters and no son. How will you convince Mohan
that his wife has no role in giving birth to daughters only so that she should not be blamed for it. Further, females are
rather more important component of society, What values are involved in this advice?
12
131 Sex determination by chromosomes in human and Drosophila is through.
A. ( x x-x y )
B. XX-XO
c. zz-zw
D. Both A and E
12
132 With the help of a chart, explain the
method of sex determination in
honeybees.
12
133 Which one correctly determines the
( operatorname{sex} ? )
A. ( x 0 ) condition in Turner’s syndrome determines female ( operatorname{sex} )
B. Homozygous XX produce male in Drosophila
C. Homozygous zz determine female sex in birds
D. ( times 0 ) determines male sex in Grasshopper
12
134 A male child will be born if
A. Father is healthy.
B. Mother is well fed during pregnancy.
C . Genetic composition of child has XY set of chromosomes.
D. Genetic composition of child has ( X X ) set of chromosomes.
12
135 Two independent monohybrid crosses were carried out involving a tall pea plant with a dwarf pea plant. In the first cross, the offspring population had equal number of tall and dwarf plants, whereas in the second cross it was
different. Work out the crosses, and explain giving reasons for the difference in the offspring populations.
12
136 Which one of the following conditions correctly describes the manner of determining the sex in the given example?
A. Homozygous sex chromosomes (XX) produce male in Drosophila.
B. Homozygous sex chromosomes (ZZ) determine female sex in birds
c. xo type of sex chromosomes determine male sex in grasshopper.
D. xo condition in humans as found in Turner Syndrome determines female sex
12
137 Which of the following character was not selected by Mendel in his experiment?
A. Plant height
B. Plant colour
c. Pod shape
D. Pod colour
12
138 Describe haplodiploid sex determination system in honey bees. 12
139 Mother is responsible for the sex of a baby.
A . True
B. False
12
140 Chromosome theory of ( X Y ) sex determination was proposed by.
A. Henking
B. Wilson and Stevens
c. Johannsen
D. Punnet
12
141 Rewrite and complete the following sentences by inserting the correct word
in the space indicated.
is the scientific name of garden pea, which mendel used for his
experiments.
12
142 Mendel’s experiments stand for 12
143 Trait that masks the other trait is called
as
A. Dominant
B. Recessive
c. Mutant
D. None of the above
12
144 Two Mark Questions:
Explain mechanism of sex determination in birds.
12
145 What do we call to the process of transfer of characters from parents to
the progeny?
12
146 Which one of the following traits studied by Mendel in garden pea was a recessive character?
A. Axial flower positon
B. Green cotyledon colour
c. Green pod colour
D. Yellow seed colour
12
147 A male rabbit of genotype AABBDDEE is crossed with a female rabbit of
genotype aabbddee to produce ( boldsymbol{F}_{1} ) hybrid offspring. How many genetically different gametes can be produced by
this ( F_{1} ) hybrid
( A cdot 4 )
B. 8
( c cdot 16 )
D. 32
12
148 The males of bees and wasps are
A. Haploid
B. Polyploid
( c cdot x x )
D. xo
12
149 The sex chromosomes of both male and
female are respectively
A. YY, XX
в. ( Y X, X Y )
c. ( x y, x x )
D. All of the above
12
150 The offspring of a cross between two individuals differing in at least one set of characters is called as
A. Polyploid
B. Mutant
c. Hybrid
D. Variant
12
151 If the first seven children born to a
particular pair of parents are all males, what is the probability that the eighth
child will also be a male?
A ( cdot frac{1}{2} )
в.
( c cdot frac{1}{8} )
D. ( frac{1}{16} )
12
152 Which one of the following cannot be explained on the basis of Mendel’s Law of Dominance?
A. Factor occur in pairs.
B. The discrete unit controlling a particular character is called as factor
c. out of one pair of factor one is dominant, and the other recessive
D. Alleles do not show any blending and both the characters recover as such in ( F_{2} ) generation
12
153 Branch of ‘botany’ connected with heredity and variations is
A. Genetics
B. Eugenics
c. Palaeobiology
D. Euthenics
12
154 The sex of an infant is not a case of
inheritance of characteristics.
A. True
B. False
12
155 Mendel’s conclusion was first published
in
A. Journal of plant breeding
B. Journal of genetics and plant breeding
c. Nature forschender verein
D. None of the above
12
156 A trait may be inherited, but may not be
expressed. Justify this statement with the help of a suitable example.
12
157 Which one of the following features represents a recessive character in
Mendel’s pea plants?
A. Round seed
B. Green pod colour
c. Red flower
D. Yellow pod colour
12
158 A dwarf pea plant was treated with gibberellic acid (GA), it grew as tall as the homozygous tall pea plant. If this GA-treated plant is now crossed with a pure tall pea plant then the phenotypic ratio in the next generation is likely to be
A. All dwarf.
B. 50% dwarf, 50% tall.
c. 75% tall, 25% dwarf
D. All tall
12
159 In Drosophila, the Y-chromosome does
not determine maleness but is
necessary for fertility.
A. True
B. False
12
160 The term genetics was coined by
A. Mendel
B. Bateson
c. Strasburger
D. All of the above
12
161 Which of the following is responsible for 21 trisomy in humans?
A. Pleiotropy
B. Polygenic inheritance
c. Epistasis
D. X-inactivation
E. Nondisjunction
12
162 What indication do we get by
reappearance of dwarf plant in ( F_{2} )
generation?
12
163 Shell coiling in Limnaea (snail) is an example of
A. Maternal inheritance
B. Biparental inheritance
c. Dauermodification
D. None of the above
12
164 Which of the following statement is
true?
A. Mother determines the sex of the child.
B. Father inherits the character to the son only.
C. Father inherits the character to daughter only.
D. None of the above.
12
165 A cross between two tall garden pea plants produced all tall plants. The possible genotypes of the parents are
I) ( pi, ) T
II) TT, Tt
III) ( T t, t )
IV) ( mathrm{Tt}, mathrm{Tt} )
A . ॥I, IV
B. I, IV
( c cdot 1,1 )
D. II, III
12
166 ZZ/ZW type of sex determination is
seen in
A. Platypus
B. Snails
c. cockroach
D. Peacock
12
167 When a sperm containing Y chromosome fertilises an egg with ( x ) chromosome, the zygote develops into a
child.
A. Female
B. Either male or a female
c. Male
D. No child
12
168 Chromosomes connected with sex
determination are
A. Autosomes
B. Heterosomes
c. oxysomes
D. B-chromosomes
12
169 Explain the sex determination in humans. 12
170 Which of the following true for an
offspring formed as a result of sexual
reproduction?
A. The offspring gets a full set of genes from the mother and from the father.
B. The offspring gets half the genes from the mother and half the genes from the father.
C. The offspring gets all of its genes from the father.
D. The offspring gets a random mixture of genes from the mother and father
E. The offspring gets all of its genes from the mother.
12
171 When released from ovary, human egg
contain
A. one Y chromosome
B. Two X chromosome
c. one x chromosome
D. xy chromosome
12
172 In Melandrium, the sex determination
type is
A. ( x x ) -XY type
B. XX-XO type
c. zz-zw type
D. xy-xo type
E. xo-zz type.
12
173 The largest gene in man is
A. Dystrophin
B. Insulin gene
C. Beta globin gene of haemoglobin
D. Tumor suppressor gene
E . Oncogene
12
174 Mendel is famous for his work on
A. Pisum
B. Drosophila
c. Neurospora
D. oenothera
12
175 What is meant by heredity? 12
176 How many pairs of autosomes and pairs
of sex chromosomes are present in a human being?
12
177 Which chromosome has satellite?
A. Telocentric
B. Metacentric
c. Acrocentric
D. Sub-metacentric
12
178 In human sperm, besides autosomes
the chromosome complement contains
A. ( x ) and ( y )
B. Either X or Y
c. Y only
D. x only
12
179 Who is responsible for the sex of
offspring-male of female? Why?
12
180 Heterogametic sex determination
based on the number of sex
chromosomes among the following are
A. ( X X-X O ) and ( X X-X Y ) methods
B. ( Z O-Z Z ) and ( Z W-Z Z ) methods
c. ( X X-X Y ) and ( Z W-Z Z ) methods
D. ( X X-X O ) and ( Z O-Z Z ) methods
12
181 XY sex chromosomes were discovered
by
A. Gregor Johann Mendel
B. M.J.D. White
c. Nettie Stevens
D. Robert Brown
12
182 Which out of these have genetic
complement ( 44+X ? )
( A cdot A )
B. B
( c cdot c )
D.
12
183 A zygote which has inherited a ( Y ) chromosome from the father will
develop into
( A cdot A ) boy
B. A girl
c. Anyone of the above
D. None of the above
12
184 Sex of a human child is determined by
A. Size of the egg at the time of fertilization
B. Size of the sperm at the time of fertilization
c. Sex chromosome of father
D. Sex chromosome of mother
12
185 What is a monohybrid cross? What is the ratio of tall and dwarf plants
obtained in ( F_{2} ) generation? Represent
the same with the help of a checker board.
12
186 If the cell of an organism heterozygous for two pairs of genes represented by ( x x, z z ) undergoes meiosis, then the
possible genotypic combination of
gametes will be
A. ( x z ; x z ; x z ; x z )
B. ( x z ; x z ; x z )
c. ( x x ; Z z ; x z )
D. Data incomplete
12
187 Who wrote the book ‘Genetics and
Origin of Species’?
A. R.A. Fisher
B. G.L. stebbins
c. T.H. Dobzhansky
D. J.B.S. Haldane
12
188 Explain sex determination in humans with a neat labelled diagram. 12
189 A family has five girls and no son, the probability of the occurance of son in 6
( t h ) child is
A ( cdot 1 / 2 )
B. 1/5
( c )
D. No chance
12
190 Which of the following explains, how
progeny can possess the combinations of traits that none of the parent
possessed?
A. Chromosome theory
B. Polygenic inheritance
c. Law of segregation
D. Law of independent assortment
12
191 What is the inheritance of colour
blindness of both parents having a normal vision but mother having a recessive gene for colour blindness?
A. Son – 50%; Daughter – nil
B. Son-100%; Daughter-nil
c. son – nil ; Daughter – 100%
D. son-nil; Daughter-nil
12
192 How does sex determination take place in human beings? 12
193 In human beings, sex is determined
A. Before fertilization of ovum
B. During 6th week of foetal life when androgens are produced
C. At the time of fertilization of ovum
D. During 7th and 8th weeks of foetal life when gonads differentiate into testis and ovary
12
194 Pre-natal sex determination has been
prohibited by law. State the necessity of inforcement of this law.
12
195 A cross done between a homozygous recessive and a heterozygous plant is called as
A. Monohybrid cross
B. Dihybrid cross
c. Test cross
D. Back cross
12
196 How is the sex of an offspring determined in humans?
A. Sex chromosome of mother
B. Size of ovum
c. Size of sperm
D. Sex chromosome of father
12
197 Both the parents contribute equal
amount of material to the
offspring.
A. Genetic
B. RNAA
c. Phenotypic
D. None of the above
12
198 Two Mark Questions:
Differentiate between ZZ and XY type of sex determination mechanism.
12
199 A zygote which has an ( X ) chromosome inherited from the father will develop
into a
( A cdot B O y )
B. Girl
c. ( x ) chromosome does not determine the sex of a child
D. Either boy or girl
12
200 What is inheritance 12
201 In a pea plant, wrinkling of seeds is due to nonformation of starch, because of the absence of
A. Amylase
B. Invertase
c. Branching enzyme
D. Diastase
12
202 The F2 generation will show maximum percentage of allele.
A. Dual
B. Recessive
c. Dominant
D. None of the above
12
203 Which condition zygotic cell will form normal human female child?
A. ( x x ) chromosomes
B. Y-chromosome
c. x-chromosome
D. xy chromosomes
12
204 Gametes are never hybrid’. This
statement is law of
A. Dominance
B. Independent assortment
c. Segregation
D. Random fertilization
12
205 Is it right to consider the mother responsible for a girl child? 12
206 Very short answer type.
Under what conditions does Mendels
law of independent assortment apply?
12
207 Sex is determined by different factors in various species.
A . True
B. False
12
208 Which one of the following pairs is not of a contrasting character?
A. Tall and dwarf
B. Axial and terminal
c. Green and yellow
D. Round and light
12
209 Two crosses between the same pair of genotypes or phenotypes in which the sources of the gametes are reversed in one cross, is known as
A. Test cross
B. Reciprocal cross
c. Dihybrid cross
D. Reverse cross
12
210 Foetal sex is determined by examining
cells from amniotic fluid looking for
A. Chiasmata
B. Barr bodies and sex chromosomes
c. only Barr bodies
D. Drumsticks
12
211 On crossing two heterozygous tall plants (Tt), a total of 500 plants were
Obtained in ( F_{1} ) generation. What will be
the respective number of tall and
dwarf plants obtained in ( F_{1} ) generation?
A. 375, 125
B. 250, 250
c. 475,25
D. 350, 150
12
212 Mendel’s principles are related to
A. Evolution
B. Reproduction
C. Variations
D. Heredity
12
213 X0 type of sex determination and XY type of sex determination are the
examples of
A. Male heterogamete
B. Female heterogamete
c. Male homogametic
D. Both B and C
12
214 Which one of the following traits of garden pea, studied by Mendel, was a recessive feature?
A. Axial flower position
B. Green seed colour
c. Green pod colour
D. Round seed shape
12
215 Principles or laws of inheritance were
enunciated by
A. Mendel
B. Morgan
c. Bateson
D. Punnet
12
216 Who rediscovered mendel’s work? 12
217 42. When a single gene controls the
expression of more than one
character, it is said to be
(1) Heterotrophic
(2) Autotrophic
(3) Allotropic
(4) Pleiotropic
12
218 Mendel studied the inheritance
patterns of 12 different pairs of
characters of the pea plant. He could
ascertain the independent assortment
for only 7 of these 12 pairs of characters
by repeated experiments. What can be
deduced from this?
A. The pea plant could have atleast seven pairs of chromosomes.
B. The pea plant can have a maximum of seven pairs of chromosomes.
C. The pea plant has exactly seven pairs of chromosomes.
D. The pea plant can have haploid chromosome number between 7 and 12 only.
12
219 Mendel studied seven contrasting characters for his breeding experiment with a pea. Which of the following characters he did not use?
A. Pod shape
B. Leaf shape
c. Plant height
D. Pod colour
12
220 Which one of the following correctly describes the manner of determining
the sex in the given examples?
A. Homozygous sex chromosomes (XX) produce male in Drosophila.
B. Homozygous sex chromosomes (ZZ) determine female sex in birds
c. xo type of sex chromosomes determine male sex in grasshopper.
D. xo condition in humans as found in Turner’s syndrome, determines female sex
12
221 Which of the following is incorrect regarding ZW-ZZ type of sex determination?
A. It occurs in birds and some reptiles.
B. Females are homogametic and males are heterogametic.
c. sex ratio is produced in the offsprings.
D. All of the above
12
222 Which condition of zygote cell will lead to birth of a normal human female child
A. one X-chromosome
B. one ( x ) and one ( Y ) chromosome
c. two X-chromosomes
D. one Y-chromosome
12
223 A woman has an ( X ) linked condition on
one of her ( mathrm{X} ) chromosomes. This chromosome can be inherited by
A. only grandchildren
B. Only daughter
c. Both sons and daughters
D. Only sons
12
224 Which of the following conditions
correctly describes the manner of
determining the sex in a given
example?
A. ( x ) O condition in humans as found in Klinefelter’s
syndrome determines female sex
B. Homozygous sex chromosomes zZ determines female sex in birds
C. ( X O ) type of sex determines male sex in grasshopper
D. Homozygous sex chromosomes ( X X ) produce male in Drosophila
12
225 Which of the following conditions correctly describes the manner of determining the sex in the given example?
A. ( X O ) type of sex determines male sex in grasshopper
B. ( X O ) condition in humans as found in Klinefelter’s syndrome determines female sex
c. Homozygous sex chromosome ( X X ) produce male in Drosophila
D. Homozygous sex chromosome ( Z Z ) determine female ( operatorname{sex} ) in birds
12
226 In male grasshoppers and moths, there are two pairs of autosomes and
A. ( x ) only
B. x and
c. Y only
D. None of the above
12
227 During the fusion of the male and female gametes, the male chromosome Y fused with the X chromosome of the
female. The offspring born will be
A. Boy
B. Girl
c. Twins
D. None of these
12

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