Genetics Most Important Questions For Neet 2021 Biology

1. In SCA the defect is caused by the substitution of Glu by Val of the Beta globin chain of Haemoglobin molecule. The normal Beta chain of Haemoglobin is

(A) Val-His-Leu-Thr-Pro-Glu-Glu

(B) Val-His-Leu-Thr-Val-Glu-Glu

(C) Val-His-Leu-Thr-Pro-Val-Glu

(D) Val-His-Leu-Thr-Pro-Val-Val

2. In Morgan’s experiments on linkage the percentage of white eyed miniature winged recombinants in F2 generation is

(A) 1.3 

(B) 62.8

(C) 37.2 

(D) 73.2

3. Which chromosome set is found in male Grasshopper?

(A) XY 

(B) XO

(C) YY 

(D) X X

4. Which of the following is not a Mendelian disorder

(A) Turner’s syndrome

(B) Thalassemia

(C) Haemophilia

(D) Cystic fibrosis.

5. An inborn error of metabolism which eventually affects

mental development is

(A) Albinism

(B) Phenylketonuria

(C) Anaemia

(D) Bleeder’s disease

6. A mutation in DNA molecule involving replacement of one nucleotide base pair with another is

(A) Point mutaiton

(B) Frame-shift mutation

(C) Deletion mutaiton

(D) A transposon

7. Phenotypically females having rudimentary ovaries, under developed breasts, short stature suggests

(A) Down’s syndrome

(B) Klinefelter’s syndrome

(C) Turner’s syndrome

(D) Haemophilic syndrome

8. If haploid chromosome number is 10, the monosomic number shall be

(A) 9 

(B) 18

(C) 11 

(D) 19

9. A monosomic organism can best be represented as

(A) 2n + 1 

(B) 2n+2

(C) n+1 

(D) 2n-1

10. The graphical represnation to calculate the probability of all possible genotypes of offspring in a genetic cross is called

(A) Pedigree analysis

(B) Punnet square

(C) Chromosome map

(D) Genotypic ratio

11. Which is connected with multiple phenotypes?

(A) Epistasis

(B) Pleiotropy

(C) Polygenic inheritance

(D) Mutations.

12. 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.

13. ABO blood group system is due to

(A) Multifactor inheritance

(B) Incomplete dominance

(C) Multiple allelism

(D) Epistasis.

14. In humans, height shows a lot of variation. It is an example of

(A) Multiple alleles

(B) Pleiotropic inheritance

(C) Polygenic inheritance

(D) Co-dominance.

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

(A) Autosomal dominant

(B) Autosomal recessive

(C) Sex-linked dominant

(D) Sex-linked recessive.

16. The chromosomes other than sex chromosomes are called

(A) Autosomes 

(B) Heterosomes

(C) Karyosomes 

(D) None of the above.

17. Defect in amino acid metabolism may result in

(A) Porphyria

(B) Phenylketonuria

(C) Wilson’s disease

(D) Tay Sach's disease.

18. Haemophilia is a genetic disorder in which

(A) Blood clots in blood vessels

(B) There is delayed coagulation of blood

(C) Blood fails to coagulate

(D) Blood cell count falls.

19. In incomplete dominance, the ratio which not deviates from the mendelian monohybrid cross-

(A) Genotypic ratio 

(B) Phenotypic ratio

(C) Both 

(D) Either A or B.

20. Number of genotypes found in F2 progeny of a dihybrid cross is

(A) 9 

(B) 16

(C) 3 

(D) 4.

21. Test cross is a cross between

(A) Hybrid x Dominant parent (Tt x TT)

(B) Hybrid x Recessive parent (Tt x tt)

(C) Hybrid x Hybrid (Tt x Tt)

(D) All the above.

22. Sahiwal cow developed through

(A) Artificial Selection

(B) Sexual reproduction & Natural Selection

(C) Domestication and Artificial Selection

(D) Artificial Selection and Domestication

23. Colour blindness occurs due to

(A) Recessive gene on X-chromosome

(B) Dominant gene on X-Chromosome

(C) Recessive gene on an autosome

(D) Dominant gene on an autosome.

24. In Drosophila female has a pair of chromosomes

(A) ZZ 

(B) XX

(C) YY 

(D) ZW.

25. Genetic maps of chromosomes are based on the frequency of

(A) Nondisjunction

(B) Translocation

(C) Linkage

(D) Genetic recombination.

26. Klinefelter’s syndrome is due to sex complement of

(A) XO 

(B) XY

(C) XXY 

(D) XYY

27. A sex link trait/disease is

(A) Colour blindness/haemophilia

(B) Nightblindness/albinism

(C) Myxodema / beriberi

(D) Deafness/tylosis.

28. Loss of a single chromosome produces a condition called

(A) Haploidy 

(B) Nullisomy

(C) Trisomy 

(D) Monosomy

29. Which has an additional X-chromosome

(A) Turner’s syndrome

(B) Down’s syndrome

(C) Klinefelter’s syndrome

(D) Super female.

30. Gynaecomastia is a symptom of

(A) Turner’s syndrome

(B) Klinefeter’s syndrome

(C) Down’s syndrome

(D) SARS.

31. Qeen Victoria of England was

(A) Haemophilic carrier

(B) Colour blind

(C) AIDS patient

(D) Thalassemic.

32. Sickle cell anemia is an example of

(A) Epistasis

(B) Codominance

(C) Pleiotropy

(D) Incomplete dominance

33. The ratio of 9 : 3 : 3: 1 is due to

(A) Segregation of characters

(B) Independent assortment of genes

(C) Crossing over of chromosomes

(D) Homologous pairing between chromosomes.

34. Independent assortment can be deduced from

(A) Monohybrid cross

(B) Test cross

(C) Back cross

(D) Dihybird cross

35. Which trait was not incorporated by Mendel for his experiments?

(A) Colour of Pea seed

(B) Colour of Pea flower

(C) Colour of Pea plant /Size of Pea seed

(D) Colour of Pea pod.

36. Alleles are

(A) Alternate forms of a gene

(B) Pairs of sex chromosomes

(C) Homologous chromosomes

(D) None of the above.

37. A gamete normally contains

(A) Many alleles of a gene

(B) All alleles of a gene

(C) Two alleles of a gene

(D) One allele of a gene.