This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Biology > Class 12 Biology Chapter 5 Principles Of Inheritance And Variation – Quiz 6 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 6 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Scientist who proposed genetic control of Rh factor A) Landsteiner. B) Louis Pasteur. C) Fisher and Rays. D) Flemming. Show Answer Correct Answer: C) Fisher and Rays. 2. Number of autosomes present in liver cells of a human female is A) 22 pairs. B) 23 autosomes. C) 22 autosomes. D) 23 pairs. Show Answer Correct Answer: A) 22 pairs. 3. What is the ratio of dominant to recessive traits in the F2 generation according to Mendel's experiments? A) 2:1. B) 1:1. C) 4:1. D) 3:1. Show Answer Correct Answer: D) 3:1. 4. In which of the following cases are maximum types of gametes possible? A) AaBb. B) AaBb. C) AABB. D) AABb. Show Answer Correct Answer: A) AaBb. 5. When a single gene causes more than one effect, it is called A) Multiple allele. B) Pleiotropy. C) Polygenes. D) Quantitative inheritance. Show Answer Correct Answer: B) Pleiotropy. 6. Gene I in humans is responsible for determining the? A) Skin colour. B) Height. C) Antirrhinum flower colour. D) Sugar polymer on plasma membrane of red blood cell. Show Answer Correct Answer: D) Sugar polymer on plasma membrane of red blood cell. 7. The characters which appear in the first filial generation are called A) Recessive characters. B) Dominant characters. C) Holandric characters. D) Lethal characters. Show Answer Correct Answer: B) Dominant characters. 8. How many different kinds of gametes will be produced by a plant having the genotype AABbCC A) 2. B) 4. C) 9. D) 3. Show Answer Correct Answer: A) 2. 9. An individual affected by phenylketonuria lacks an enzyme that converts the amino acid ..... into ..... A) Homogentistic acid, phenylalanine. B) Phenylalanine, tyrosine. C) Homogentisic acid, tyrosine. D) Tyrosine, phenylalanine. Show Answer Correct Answer: B) Phenylalanine, tyrosine. 10. The colour based contrasting traits in seven contrasting pairs, studied by Mendel in pea plant were A) 1. B) 4. C) 3. D) 2. Show Answer Correct Answer: C) 3. 11. An individual depicts following symptoms:i.Short stature with small round head ii.Congenital heart diseaseiii.Mental and physical retardationThe individual is diagnosed with A) Phenylketonuria. B) Klinefelter's syndrome. C) Down's syndrome. D) Turner's syndrome. Show Answer Correct Answer: C) Down's syndrome. 12. What type of mutation is a frame-shift mutation? A) A change in a single nucleotide. B) A substitution of one base for another. C) A mutation that does not affect the protein. D) An insertion or deletion of nucleotides. Show Answer Correct Answer: D) An insertion or deletion of nucleotides. 13. One of a number of different forms of a gene. The two ..... for pea color is yellow and green. A) Trait. B) Allele. C) Self-pollination. D) Cross-pollination. Show Answer Correct Answer: B) Allele. 14. The chromosomes responsible for the determination of sex are known as A) Autosomes. B) Allosomes. C) Heterosis. D) Multiple alleles. Show Answer Correct Answer: B) Allosomes. 15. Test cross involves A) Crossing between two genotypes with dominant traits. B) Crossing F$_{1 }$hybrid with a double recessive genotype. C) Crossing between two F$_{1 }$hybrids. D) Crossing between two genotypes with recessive traits. Show Answer Correct Answer: B) Crossing F$_{1 }$hybrid with a double recessive genotype. 16. Coat color in cow is an example of A) Multiple alleles. B) Incomplete dominance. C) Co-dominance. D) Supplementary genes. Show Answer Correct Answer: C) Co-dominance. 17. A true breeding plant is A) One that is able to breed on its own. B) Produced due to cross-pollination between unrelated plants. C) Near homozygous and produces offsprings of its own type. D) Always homozygous in its genetic constitution. Show Answer Correct Answer: D) Always homozygous in its genetic constitution. 18. Which of the following shows the characteristics of F1 progeny plants in Mendel's monohybrid cross experiments? A) F1 resembled either one of the parents and the trait of the other parent was not seen. B) F1 did not resemble either of the parents, and was in between the two. C) F1 resembled both the parents. D) None of the above. Show Answer Correct Answer: A) F1 resembled either one of the parents and the trait of the other parent was not seen. 19. What is the probability of production of dwarf offsprings in a cross between two heterozygous tall pea plants? A) 100%. B) 50%. C) 25%. D) Zero. Show Answer Correct Answer: C) 25%. 20. What contributed to Mendel's success? I. Selection of pureline pea varieties. II. Knowledge of history. III. Selecting one character at a time. IV. Statistical analysis and mathematicallogic. Choose the correct option A) I, II, III and IV. B) II and III. C) I, III and IV. D) II, III and IV. Show Answer Correct Answer: C) I, III and IV. 21. The genotype of a plant is AaBb. How many different type of genotype in gametes it can produce? A) Four. B) Two. C) Eight. D) One. Show Answer Correct Answer: A) Four. 22. What is the F1 generation in Mendel's experiments? A) Offspring generation. B) Second filial generation. C) First filial generation. D) Parental generation. Show Answer Correct Answer: C) First filial generation. 23. Sally's genotype is heterozygous. Her genotype is written as ..... A) D D. B) D d. C) D d. D) None of the above. Show Answer Correct Answer: B) D d. 24. Who proposed Chromosomal Theory of inheritance- A) In 1992, Walter Sutton and Theodore Crick. B) In 1902, Walter Sutton and Theodore Boveri. C) In 1902, Walter Sutton and Theodore Crick. D) In 1992, Walter Sutton and Theodore Boveri. Show Answer Correct Answer: B) In 1902, Walter Sutton and Theodore Boveri. 25. In F2 Mendelian population of 100 pea plants, how many are expected to be pure tall? A) 25. B) 75. C) 50. D) 100. Show Answer Correct Answer: A) 25. 26. Depending upon the distance between any two genes which is inversely proportional to the strength of linkage, cross overs will vary from A) 0-50%. B) 100-150%. C) 50-100%. D) 75-100%. Show Answer Correct Answer: A) 0-50%. 27. Which is a sex influenced trait? A) Porcupine skin in man. B) Hairy pinna. C) Colourblindness in man. D) Baldness in man. Show Answer Correct Answer: D) Baldness in man. 28. Insertion or deletion of a single base causes A) Frame-shift mutation. B) Inversion mutation. C) Transversion mutation. D) Transition mutation. Show Answer Correct Answer: A) Frame-shift mutation. 29. Seven different characters selected by Mendel was located on how many chromosomes? A) 4. B) 2. C) 7. D) 1. Show Answer Correct Answer: A) 4. 30. A gene showing codominance 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. Show Answer Correct Answer: B) Both alleles independently expressed in the heterozygote. 31. Select the correct statements regarding honeybees.(i) The queen bee and the worker bees develop from fertilized eggs and are sexually females.(ii) Males (drones develop parthenogenetically from unfertilized eggs.(iii) Queen bee feeds upon royal jelly and the worker bees feed upon bee bread. A) (i) and (ii) only. B) (ii) and (iii) only. C) (i) and (iii) only. D) (i), (ii) and (iii). Show Answer Correct Answer: D) (i), (ii) and (iii). 32. Life cycle of fruit fly(Drosophila) is- A) 4-5 days. B) 9-10days. C) 12-14 days. D) 3-4 days. Show Answer Correct Answer: C) 12-14 days. 33. Strength of the linkage between the two genes is A) Inversely proportionate to the distance between them. B) Depend upon the size of chromosomes. C) Proportionate to the distance between them. D) Depend on the chromosomes. Show Answer Correct Answer: A) Inversely proportionate to the distance between them. 34. A yellow seeded true breeding plant is crossed with green seeded true breeding plant. F1 plants were yellow seeded showing that allele for yellow seed is A) Dominant. B) Codominant. C) Heterozygous. D) Lethal. Show Answer Correct Answer: A) Dominant. 35. Which one of the following conditions in humans is correctly matched with its chromosomal abnormality/linkage? A) Down's syndrome-44 autosomes + XO. B) Klinefelter's syndrome-44 autosomes + XXY. C) Erythroblastosis fetalis-X-linked. D) Colour blindness-Y-linked. Show Answer Correct Answer: B) Klinefelter's syndrome-44 autosomes + XXY. 36. Genes do not occur in pair in A) Endosperm cells. B) Somatic cell. C) Gametes. D) Zygote. Show Answer Correct Answer: C) Gametes. 37. In XO type of sex determination A) Males produce two different types of gametes. B) Females produce gametes with Y chromosome. C) Females produce two different types of gametes. D) Male produce gametes with Y chromosome. Show Answer Correct Answer: A) Males produce two different types of gametes. 38. What is the ratio of one pair of contrasting character in F2 of a dihybrid ratio. A) 1:2:2:4:1:2:1:2:1. B) 5:3. C) 3:1. D) 9:3:3:1. Show Answer Correct Answer: C) 3:1. 39. In sickle cell anaemia, A) Glutamic acid is replaced by valine. B) Glutamic acid is replaced by tyrosine. C) Glutamic acid is replaced by phenylalanine. D) Valine is replaced by glutamic acid. Show Answer Correct Answer: A) Glutamic acid is replaced by valine. 40. Out of two alleles of the same gene, only one finds morphological expression. This phenomenon is A) Codominance. B) Incomplete dominance. C) Complementary. D) Dominance. Show Answer Correct Answer: D) Dominance. 41. In certain plant, yellow fruit colour (Y) is dominant to green fruit colour (y) and round shape (R) is dominant to oval shape (r). The two genes involved are located on different chromosomes.Which of the following is correct for the condition when plant YyRr is back crossed with the double recessive parent? A) 9:3:3:1 ratio of phenotypes only. B) 9:3:3:1 ratio of genotypes only. C) 1:1:1:1 ratio of phenotypes only. D) 1:1:1:1 ratio of phenotypes and genotypes. Show Answer Correct Answer: D) 1:1:1:1 ratio of phenotypes and genotypes. 42. A cross between two tall plants resulted in offspring having few dwarf plants. What would be the genotypes of both the parents? A) TT and Tt. B) Tt and Tt. C) TT and TT. D) Tt and tt. Show Answer Correct Answer: B) Tt and Tt. 43. Physical association of 2 or more genes on a chromosome is- A) Assortment. B) Linkage. C) Crossing over. D) Recombinantion. Show Answer Correct Answer: B) Linkage. 44. Conditions of a karyotype 2n $\pm$ $\pm$ A) Aneuploidy. B) Polyploidy. C) Allopolyploidy. D) Monosomy. Show Answer Correct Answer: A) Aneuploidy. 45. A diseased man marries a normal woman. They get three daughter and five sons. All the daughters were diseased and sons were normal. The gene of this disease is? A) Sex linked dominant. B) Sex linked recessive. C) Autosomal dominant. D) Sex limited character. Show Answer Correct Answer: A) Sex linked dominant. 46. If a genetic disease is transferred from a phenotypically normal but carrierfemale to only some of the male progeny, the disease is: A) Sex-linked dominant. B) Autosomal dominant. C) Sex-linked recessive. D) Autosomal recessive. Show Answer Correct Answer: C) Sex-linked recessive. 47. Distance between the genes and percentage of recombination shows: A) A direct relationship. B) An inverse relationship. C) A parallel relationship. D) No relationship. Show Answer Correct Answer: A) A direct relationship. 48. Distance between genes and advantages of recombination shows A) Direct relationship. B) Inverse relationship. C) Parallel relationship. D) No relationship. Show Answer Correct Answer: A) Direct relationship. 49. In sickle-cell anemia, diseased condition occurred due to replacement of amino acid A) Val to Glu. B) Glu to Val. C) Pro to Val. D) None of the above. Show Answer Correct Answer: B) Glu to Val. 50. If a haemophilic man marries a carrier woman then which of the following holds true for their progenies? A) 50% daughters are carrier and 50% are haemophilic. B) All the daughters are haemophilic. C) All sons are haemophilic and all daughters are normal. D) All sons normal, all daughters carriers. Show Answer Correct Answer: A) 50% daughters are carrier and 50% are haemophilic. 51. Red green colourblindness is a sex linked trait. Which of the given statements is not correct regarding colourblindness? A) It is more common in males than in females. B) Homozygous recessive condition is required for the expression of colourblindness in female. C) Males can carriers of the trait. D) Colourblind women always have colourblind father and always produce colourblind son. Show Answer Correct Answer: C) Males can carriers of the trait. 52. Choose the wrong statement regarding thalassemia. A) Autosomal recessive disorder. B) Beta thalassemia is the common type. C) Excessive destruction of WBC. D) Gene is located in chromosome 11. Show Answer Correct Answer: C) Excessive destruction of WBC. 53. How many pairs of contrasting characters in pea plants were studied by Mendelssohn in his experiments A) 7. B) 8. C) 6. D) 5. Show Answer Correct Answer: A) 7. 54. A woman with normal vision has a colourblind father. she marries a colourblind man. What proportion of their children will be colourblind? A) 25%. B) 100%. C) 50%. D) 0%. Show Answer Correct Answer: C) 50%. 55. An organism is a hybrid genotype (Tt) but is appears tall instead of short. A) Law of Dominance. B) Law of Segregation. C) Law of Independent Assortment. D) None of the above. Show Answer Correct Answer: A) Law of Dominance. 56. 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) 1:1 sex ratio is produced in the offsprings. D) All of these. Show Answer Correct Answer: B) Females are homogametic and males are heterogametic. 57. A cross between F$_{1}$ hybrid and its homozygous recessive parent is called A) Test cross. B) Out cross. C) Dihybrid cross. D) Monohybrid cross. Show Answer Correct Answer: A) Test cross. 58. If a diploid organism consists of 20 chromosomes, number of chromosomes in nullisomic condition will be A) 18. B) 19. C) 22. D) 23. Show Answer Correct Answer: A) 18. 59. Select the incorrect statement regarding pedigree analysis. A) Solid symbols show unaffected individuals. B) Proband is the person from which case history starts. C) It is useful for genetic counsellors. D) It is an analysis of traits in several generation of a family. Show Answer Correct Answer: A) Solid symbols show unaffected individuals. 60. Colour blindness in humans A) Results in defect in either red or green cone of eyes. B) Is caused due to the mutation in gene found on X-chromosome. C) Affects males more frequently than females. D) All of the above. Show Answer Correct Answer: D) All of the above. ← PreviousNext →Related QuizzesScience QuizzesClass 12 QuizzesClass 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 1Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 2Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 3Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 4Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 5Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 7Class 12 Biology Chapter 5 Principles Of Inheritance And Variation Quiz 8Class 12 Biology Chapter 1 Reproduction In Organisms Quiz 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books