Principles of Inheritance and Variation class 12 MCQs

Principles of Inheritance and Variation class 12 English MCQ Question and Answer

Principles of Inheritance and Variation class 12 MCQs taken from CBSE Syllabus Chapter 5 These MCQs are prepared latest Exams pattern.Read all the MCQs carefully it will Improve your Understanding level.

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Principles of Inheritance and Variation class 12 MCQs

Question:1 Cuase of chromosomal mutation.

  1. Euploidy
  2. Polyloidy
  3. Physical effect
  4. all of these

Question:2 Mendal was born in .

  1. 17th century
  2. 18th century
  3. 19th century
  4. 8th century

Question:3 Two genes very close on a chromosome will show .

  1. No crossing over
  2. high crossing over
  3. Hardly a crossing over
  4. only double crossing over

Question:4 First geneticist/father of genetics was.

  1. De vries
  2. Mendel
  3. Darwin
  4. Morgan

Question:5 Individual with into identical alleles is.

  1. Hybrid
  2. Dominant
  3. homozgous
  4. heterozgous

Question:6 Mendal’s law can be applicable only when.

  1. Characters are linked
  2. parents are pore breed
  3. F1 generation in monohybrid cross show 2 type of individuals
  4. One pair of contrasing characters depends on another pair.

Question:7 A true hybrid condition is.

  1. tt Rr
  2. Tr rr
  3. tt rr
  4. Tr Rr

Question:8 The aliele which is unable to express its effect in the presence of another is called.

  1. Co-dominant
  2. supplementary
  3. Complementary
  4. Recessive

Question:9 Most of the mutations are.

  1. Recessive
  2. harmful
  3. Germinal
  4. All of these

Question:10 smallest segment of genetic material affected by mutationis .

  1. Recon
  2. Cistron
  3. Muton
  4. Exon

Question:11 Genes located on V-chromosome are.

  1. Mutant genes
  2. Autosomal genes
  3. Holandric genes
  4. sex-linked genes

Question:12 A strong mutagen is .

  1. Cold
  2. heat
  3. water
  4. X-rays

Question:13 A point mutation is.

  1. Thalassemia
  2. sickle-cell anaemia
  3. Down’s syndrome
  4. Night blindness

Question:14 Mendel’s second law is of the law of .

  1. segregation
  2. Dominance
  3. Polygenic Inheritance
  4. Independent assortment

Question:15 An organism with two unlike genes of a trait is called.

  1. homozygous
  2. Heterozygous
  3. Both of these
  4. None of these

Question:16 Mendel’s laws were discoevered by .

  1. Correns
  2. shermak
  3. de meris
  4. all of these

Question:17 Mendel’s formulated the law of purity of gametes on the basis of .

  1. Test cross
  2. back cross
  3. monohybrid cross
  4. dihybrid cross

Question:18 tt mates with Tt. what will be characteristic of offspring.

  1. 75% uneffective
  2. 50% uneffective
  3. 25% uneffective
  4. all of these

Question:19 Exception of medel’s law is

  1. Dominance
  2. Purity of gametes
  3. Linkage
  4. Independent assortment

Question:20 Haemophilia is a

  1. Mendelian disorder
  2. Chromosomal disorder
  3. Can be a and b
  4. all of these

Question:21 Down’s sydrome is a

  1. Mendelian disorder
  2. Chromosomal disorder
  3. can be both
  4. None of these

Question:22 Mendel worked on.

  1. Edible pea
  2. wild pea
  3. Garden pea
  4. None of these

Question:23 A gamete contains which of the following

  1. both alleles or a gene
  2. only one allele of a gene
  3. Al allele of a gene
  4. No allele

Question:24 Name the scientist who discovered the law of heredity.

  1. Gregor Mendel
  2. Newton
  3. Pinnett
  4. None of these

Question:25 punnett square was developed by .

  1. Mendel
  2. watson and sutton
  3. Boveri
  4. Raginald

Question:26 who intoduced chromosomal theory of interitance ?

  1. Mendel
  2. sutton
  3. Reginald
  4. Boveri

Question:27 The plant mendel used to study interitance of two genes is.

  1. Apple
  2. Mango
  3. Garden pea
  4. Potato

Question:28 Mendel published his work on interitance of character in ?

  1. 1870
  2. 1900
  3. 1865
  4. 1845

Question:29 Loss of Melanin pigment cause for.

  1. Colour-blindness
  2. Depigmentation
  3. Phenyl Ketonuria
  4. Alkaptonuria

Question:30 Genetical identification of male human is.

  1. By Nucleus
  2. by cells
  3. by Autosome
  4. by sex chronosome

Question:31 if a genetic disease is transferred from a phenotypically normal but carrier female to only some. of the male progeny, the disease is.

  1. Autosomal dominant
  2. Autosomal recessive
  3. sex-linked dominant
  4. sex-linked recessive.

Question:32 In sickle cell anaemia glutamic acid is replaced by valine. which one of the following triplets codes for valine ?

  1. GGG
  2. AAG
  3. GAA
  4. GUG.

Question:33 ZZ/ ZW type of sex determination is seen in.

  1. platypus
  2. snails
  3. Cockroach
  4. peacock.

Question:34 which of the following will not result in variations among siblings ?

  1. Independent assortment of genes
  2. Crossing over
  3. Linkage
  4. Mutation.

Question:35 Occasionally, a single gene may express more than one effect’ the phenomeon is called

  1. Multiple allelism
  2. Mosacisim
  3. Pleiotropy
  4. Polygeny.

Question:36 The inheritance pattern of a gene over generations among human is studied by the pdigree analysis is equivalent to.

  1. quantative trait
  2. Mendelian trait
  3. polygenic trait
  4. maternal trait.

MCQs Answers

Question NoAnswer Question NoAnswer
Q & A

Question:1 How is the phenotypic ratio of F2-generation in a dihybrid cross is different from monohybrid cross? (All India 2012)

Answer: In a monohybrid cross, the phenotypic ratio of F2-generation is 3 : 1, whereas in dihybrid cross, the pheonotypic ratio of F2-generation is 9 : 3 : 3 : 1.

Question:2 Explain the laws that Mendel derived from his monohybrid crosses. (Delhi 2016C)

Answer: From mbnohybrid crosses, Mendel derived law of dominance and law of segregation.
Refer to text on page no. 92 for detailed description of these laws.

Question:3  State a difference between a gene and an allele

Answer: Gene contains information that is required to express a particular trait whereas alleles are alternating forms of a gene and are the code for a pair of contrasting traits for e.g., for plant height has two alleles – for tallness and dwarfness.

Question:4 Why, in a test cross, did Mendel cross a tall pea plant with a dwarf pea plant only?

Answer :To determine the genotype of the tall plant, whether it is homozygous dominant or heterozygous, as dwarfness is a recessive trait which is expressed only in homozygous condition and he was sure of genotype of dwarf plant.

Read Also
  1. Chapter 1: Reproduction in Organisms class 12 MCQ
  2. Chapter 2: Sexual Reproduction Flowering plants class 12 MCQ
  3. Chapter 3: Human Reproduction class 12 MCQ
  4. Chapter 4: Reproductive Health class 12 MCQ


Principles of Inheritance and Variation class 12 MCQs These are very Important MCQs Please Read all the questions and give the answer at yourself first than you can check my answer if your answer is correct so congratulation but if your answer is incorrect so don’t worry you can practice more

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