Principles of Inheritance and Variation MCQs Mock Test of Class 12th Biology

Question 1. Select the disease which is caused by recessive autosomal genes when present in homozygous conditions.

Question 2. Which of the following trait is controlled by dominant autosomal genes ?

Question 3. Failure of segregation of chromatids during cell division results in the gain or loss of chromosomes, this is called as

Question 4. Trisomy is represented by

Question 5. Mongolism is a genetic disorder which is caused by the presence of an extra chromosome number

Question 6. A cross between two tall plants resulted in offspring having few dwarf plants. What would be the genotypes of both the parents ?

Question 7. Chromosome maps/genetic maps were first prepared by

Question 8. The distance between the genes is measured by

Question 9. Which of the following is suitable for experiment on linkage ?

Question 10. Distance between the genes and percentage of recontbfnatidnshows

Question 11. In the F2 generation of a Mendelian dihybrid cross the number of phenotypes and genotypes are

Question 12. The colour based contrasting traits in seven contrasting pairs, studied by Mendel in pea plant were

Question 13. _________ pairs of contrasting traits were studied by Mendel in pea plant.

Question 14. Which of the following characters was not chosen by Mendel ?

Question 15. Genes which code for a pair of contrasting traits are known as

Question 16. A recessive allele is expressed in

Question 17. In a dihybrid cross, if you get 9 : 3 : 3 : 1 ratio it denotes that

Question 18. Which of the following will not result in variations among siblings ?

Question 19. Mendel’s Law of independent assortment holds good for genes situated on the

Question 20. Occasionally, a single gene may express more than one effect. The phenomenon is called

Question 21. The characters which appear in the first filial generation are called

Question 22. What will be the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus ?

Question 23. In a monohybrid cross between two heterozygous individuals, percentage of pure homozygous individuals obtained in F1 generation will be

Question 24. What is the probability of production of dwarf offsprings in a cross betweeen two heterozygous tall pea plants ?

Question 25. Which of the following crosses will give tall and dwarf pea plants in same proportions ?

Question 26. If a genetic disease is transferred from a phenotypically normal but carrier female to only some of the male progeny, the disease is

Question 27. In sickle cell anaemia glutamic acid is replaced by valine. Which one of the following triplets codes for valine ?

Question 28. Person having genotype IA IB would show the blood group as AB. This is because of

Question 29. ZZ/ZW type of sex determination is seen in

Question 30. Which of the following is incorrect regarding ZW – ZZ type of sex determination ?

Question 31. A couple has six daughters. What is the possibility of their having a girl next time ?

Question 32. Number of autosomes present in liver cells of a human female is

Question 33. Haplodiploidy is found in

Question 34. Rate of mutation is affected by

Question 35. Two or more independent genes present on different chromosomes which determine nearly same phenotype are called

Question 36. Select the incorrect statement regarding pedigree analysis.

Question 37. To determine the genotype of a tall plant of F2 generation, Mendel crossed this plant with a dwarf plant. This cross represents a

Question 38. Which of the following is a test cross ?

Question 39. Mendal formulated the law of purity of gametes on the basis of

Question 40. The inheritance of flower colour in Antirrhinum (dog flower) is an example of

Question 41. In Antirrhinum (dog flower), phenotypic ratio in F2 generation for the inheritance of flower colour would be

Question 42. Phenotypic and genotypic ratio is similar in case of

Question 43. What can be the blood group of offspring when both parents have AB blood group ?

Question 44. Inheritance of roan coat in cattle is an example of

Question 45. ABO blood grouping in human beings cites the example of

Question 46. In mice, Y is the dominant allele for yellow fur an y is the recessive allele for grey fur. Since Y is lethal when homozygous, the result of cross Yy × Yy will be

Question 47. How many types of gametes can be produced by a diploid organism who is heterozygous for 4 loci ?

Question 48. Which of the following is correct for the condition when plant YyRr is back crossed with the double recessive parent ?

Question 49. Law of independent assortment can be explained with the help of

Question 50. Mendel’s work was rediscovered by three scientists in the year