Please refer to the MCQ Questions for Class 12 Biology Chapter 5 Principles of Inheritance and Variation with Answers. The following Principles of Inheritance and Variation Class 12 Biology MCQ Questions has been designed based on the latest syllabus and examination pattern for Class 12. Our experts have designed MCQ Questions for Class 12 Biology with Answers for all chapters in your NCERT Class 12 Biology book.
Principles of Inheritance and Variation Class 12 MCQ Questions with Answers
See below Principles of Inheritance and Variation Class 12 Biology MCQ Questions, solve the questions and compare your answers with the solutions provided below.
Question. Which one from those given below is the period for Mendel’s hybridisation experiments?
Question. In his classic experiments on pea plants, Mendel did not use
(a) seed shape
(b) flower position
(c) seed colour
(d) pod length.
Question. How many pairs of contrasting characters in pea plants were studied by Mendel in his experiments?
Question. 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
Question. The genes controlling the seven pea characters studied by Mendel are now known to be located on how many different chromosomes?
Question. How many true breeding pea plant varieties did Mendel select as pairs, which were similar except in one character with contrasting traits?
Question. 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
Question. The ability of a gene to have multiple phenotypic effects is known as
c) Incomplete dominance
d) Incomplete dominance
Question. How many different genotypes are possible from a cross between the parents RR and rr
Question. Match the following organism with the type of sex determination found in them
Column I Column II
A) ZW-ZZ type M) Grasshopper
B) ZO-ZZ N) Drosophila
C) XX-XO O) Hen
D) XX-XY P) Butterfly
a) A- M, B-P, C- O, D-N
b) A-O, B- N, C-M, D- P
c) A-O, B-P, C-M, D-N
d) A- N, B-P, C-M, D- O
Question. “Father of experimental Genetics”
a) Gregor Mendel
c) Hugo deVries
d) Carl Correns
Question. Which is the false statement?
a) Sickle cell anemia is a recessive autosomal disorder
b) Phenylketonuria is a recessive allosomal disorder
c) Haemophilia is a recessive sex linked disorder
d) Colour blindness is a recessive allosome linked disorder
Question. If heterozygous round seeded pea plants are self pollinated, the offsprings will be
a) 75% round
b) 50% heterozygous
c) 25% rr
d) All of these
Question. Turner’s syndrome is
Question. Mendel developed his basic principles of heredity by
a) Microscopic study of chromosomes and genes
b) Mathematical analysis of the offspring of Pea plant
c) Breeding experiments with Drosophila
d) Anatomical studies of Pea plant
Question. Erythroblastosis foetalis occurs when
a) Mother is Rh negative and father is Rh positive
b) Father is Rh negative and mother is Rh positive
c) Both are Rh positive
d) Both are Rh negative
Question. When two hybrids are crossed, the percentage of recessive is
Question. Which Mendelian cross can produce two genotypes and two phenotypes?
a) Monohybrid cross
b) Monohybrid test cross
c) Incomplete dominance
Question. Which of the following disorder shows Criss cross inheritance?
b) Colour blindness
c) Erythroblastosis foetalis
d) (a) & (b)
Question. The “cri-du-chat” syndrome is caused by change in chromosome structure involving
Question. Cinderella of Genetics is
a) Pisum sativum
Question. Eyes that slant upwards with epicanthus is a characteristic of
a) Klinefelter’s syndrome
b) Turner’s syndrome
c) Down’s syndrome
d) Super female
Question. According to Mendelism, which character shows dominance?
(a) Terminal position of flower
(b) Green colour in seed coat
(c) Wrinkled seeds
(d) Green pod colour
Question. Identify the wrong statement with reference to the gene ‘I’ that controls ABO blood groups.
(a) The gene (I) has three alleles.
(b) A person will have only two of the three alleles.
(c) When IA and IB are present together, they express same type of sugar.
(d) Allele i does not produce any sugar.
Question. A gene showing co-dominance has
(a) alleles that are recessive to each other
(b) both alleles independently expressed in the heterozygote
(c) one allele dominant on the other
(d) alleles tightly linked on the same chromosome.
Question. Alleles are
(a) different molecular forms of a gene
(c) different phenotype
(d) true breeding homozygotes.
Question. Multiple alleles are present
(a) at the same locus of the chromosome
(b) on non-sister chromatids
(c) on different chromosomes
(d) at different loci on the same chromosome.
Question. A man with blood group ‘A’ marries a woman with blood group ‘B’. What are all the possible blood groups of their offspring?
(a) A, B, AB and O
(b) O only
(c) A and B only
(d) A, B and AB only
Question. Which idea is depicted by a cross in which the F1 generation resembles both the parents?
(a) Inheritance of one gene
(c) Incomplete dominance
(d) Complete dominance
Question. F2 generation in a Mendelian cross showed that both genotypic and phenotypic ratios are same as 1 : 2 : 1. It represents a case of
(b) dihybrid cross
(c) monohybrid cross with complete dominance
(d) monohybrid cross with incomplete dominance.
Question. 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.
Question. First geneticist/father of genetics was
(a) De Vries
Question. Which contribute to the success of Mendel?
(a) Qualitative analysis of data
(b) Observation of distinct inherited traits
(c) His knowledge of biology
(d) Consideration of one character at one time
Question. 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.
Question. ABO blood groups in humans are controlled by the gene I. It has three alleles – IA, IB and i. Since there are three different alleles, six different genotypes are possible. How many henotypes can occur?
Question. ABO blood grouping is controlled by gene I which has three alleles and show co-dominance. There are six genotypes. How many phenotypes in all are possible?
Question. A cross in which an organism showing a dominant phenotype is crossed with the recessive parent in order to know its genotype is called
(a) monohybrid cross
(b) back cross
(c) test cross
(d) dihybrid cross.
Question. 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 ou expect in F1 generation?
(a) 9 : 1
(b) 1 : 3
(c) 3 : 1
(d) 50 : 50
Question. A common test to find the genotype of a hybrid is by
(a) crossing of one F2 progeny 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.
Question. Test cross involves
(a) crossing between two genotypes with dominant trait
(b) crossing between two genotypes with recessive trait
(c) crossing between two F1 hybrids
(d) crossing the F1 hybrid with a double recessive genotype.
Question. 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.
Question. 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.
Question. Phenotype of an organism is the result of
(a) genotype and environment interactions
(b) mutations and linkages
(c) cytoplasmic effects and nutrition
(d) environmental changes and sexual dimorphism
Question. A gene is said to be dominant if
(a) it expresses its effect only in homozygous state
(b) it expresses its effect only in heterozygous condition
(c) it expresses its effect both in homozygous and heterozygous condition
(d) it never expresses its effect in any condition
Question. When dominant and recessive alleles express itself together it is called
Question. In hybridisation, Tt × tt gives rise to the progeny of ratio
(a) 2 : 1
(b) 1 : 2 : 1
(c) 1 : 1
(d) 1 : 2.
Question. A child’s blood group is ‘O’. The parent’s blood groups cannot be
(a) A and B
(b) A and A
(c) AB and O
(d) B and O.
Question. An organism with two identical alleles is
Question. A man of A-blood group marries a woman of AB blood group. Which type of progeny would indicate that man is heterozygous A?
Question. Multiple alleles control inheritance of
(b) colour blindness
(c) sickle cell anaemia
(d) blood groups.
Question. The contrasting pairs of factors in Mendelian crosses are called
(a) multiple alleles
Question. Mendel’s last law is
(c) independent assortment
(d) polygenic inheritance.
Question. Blue eye colour is recessive to brown eye colour. A brown eyed man whose mother was blue eyed marries a blue-eyed woman. The children will be
(a) both blue eyed and brown eyed 1 : 1
(b) all brown eyed
(c) all blue eyed
(d) blue eyed and brown eyed 3 : 1.
Question. RR (Red) Antirrhinum is crossed with white (WW) one. Offspring RW are pink. This is an example of
(b) incomplete dominance
(d) supplementary genes.
Question. tt mates with Tt. What will be characteristic of offspring?
(a) 75% recessive
(b) 50% recessive
(c) 25% recessive
(d) All dominant
Question. A child of O-group has B-group father. The genotype of father will be
Question. An allele is dominant if it is expressed in
(a) both homozygous and heterozygous states
(b) second generation
(c) heterozygous combination
(d) homozygous combination.
Question. ABO blood group system is due to
(a) multifactor inheritance
(b) incomplete dominance
(c) multiple allelism
Question. Haploids are able to express both recessive and dominant alleles/mutations because there are
(a) many alleles for each gene
(b) two alleles for each gene
(c) only one allele for each gene in the individual
(d) only one allele in a gene.
Question. Experimental verification of the chromosomal theory of inheritance was done by
Question. The mechanism that causes a gene to move from one linkage group to another is called
Question. The term “linkage” was coined by
(a) G. Mendel
(b) W. Sutton
(c) T.H. Morgan
(d) T. Boveri.
Question. The movement of a gene from one linkage group to another is called
(b) crossing over
Question. Fruit colour in squash is an example of
(a) recessive epistasis
(b) dominant epistasis
(c) complementary genes
(d) inhibitory genes.
Question. Which of the following statements is not true of two genes that show 50% recombination frequency?
(a) The gene show independent assortment.
(b) If the genes are present on the same chromosome, they undergo more than one cross-overs in every meiosis.
(c) The genes may be on different chromosomes.
(d) The genes are tightly linked.