NEET Topic-wise & A
Topic 1: MENDEL’S LAWS OF INHERITANCE
NEET: Previous Years Questions
01. Match List I with List II.
Choose the correct answer from the options given below:
(1) A-I, B-II, C-III, D-IV
(2) A-II, B-I, C-III, D-IV
(3) A-III, B-IV, C-I, D-II
(4) A-IV, B-III, C-II, D-I (NEET 2024)
✅ (3) A-III, B-IV, C-I, D-II
02. Which one of the following can be explained on the basis of Mendel's Law of Dominance?
A. Out of one pair of factors one is dominant and the other is recessive.
B. Alleles do not show any expression and both the characters appear as such in F2 generation.
C. Factors occur in pairs in normal diploid plants.
D. The discrete unit controlling a particular character is called factor.
E. The expression of only one of the parental characters is found in a monohybrid cross.
Choose the correct answer from the options given below:
(1) A, B and C only
(2) A, C, D and E only
(3) B, C and D only
(4) A, B, C, D and E (NEET 2024)
✅ (2) A, C, D and E only
03. In a plant, black seed color (BB/Bb) is dominant over white seed color (bb). In order to find out the genotype of the black seed plant, with which of the following genotype will be cross it?
(1) BB
(2) bb
(3) Bb
(4) BB/Bb (NEET 2024)
✅ (2) bb
04. The production of gametes by the parents, formation of zygotes, the F1 and F2 plants, can be understood from a diagram called:
(1) Bullet square
(2) Punch square
(3) Punnett square
(4) Net square (NEET 2021)
✅ (3) Punnett square
05. How many true breeding pea plant varieties did Mendel select as pairs, which were similar except in one character with contrasting traits?
(1) 14
(2) 8
(3) 4
(4) 2 (NEET 2020)
✅ (1) 14
06. Select the correct statement:
(1) Franklin Stahl coined the term “Linkage”
(2) Punnett square was developed by a British scientist
(3) Spliceosomes take part in translation
(4) Transduction was discovered by S. Altman (NEET 2018)
✅ (2) Punnett square was developed by a British scientist
07. Among the following characters, which one was not considered by Mendel in his experiments on pea?
(1) Trichomes-Glandular or non-glandular
(2) Seed-Green or yellow
(3) Pod-Inflated or constricted
(4) Stem-Tall or dwarf (NEET 2017)
✅ (1) Trichomes-Glandular or non-glandular
08. Which one from those given below is the period for Mendel’s hybridisation experiments?
(1) 1840-1850
(2) 1857-1869
(3) 1870-1877
(4) 1856-1863 (NEET 2017)
✅ (4) 1856-1863
09. A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant. When the F1 plants were selfed the resulting genotypes were in the ratio of
(1) 3:1 : : Tall : Dwarf
(2) 3:1 : : Dwarf : Tall
(3) 1:2:1 : :Tall homozygous: Tall heterozygous: Dwarf
(4) 1:2:1: :Tall heterozygous: Tall homozygous: Dwarf (NEET-I 2016)
✅ (3) 1:2:1 : :Tall homozygous: Tall heterozygous: Dwarf
Model Questions
10. Select the odd one out.
(1) Violet flower
(2) Round seed
(3) Yellow pod
(4) Tall stem
✅ (3) Yellow pod
11. The graphical representation to calculate probability of all genotypes of offspring in a genetic cross, is called
(1) Pedigree analysis
(2) Karyotype
(3) Punnett square
(4) Chromosome map
✅ (3) Punnett square
12. A pure tall pea plant is crossed with pure dwarf pea plant. The progeny is self-pollinated. The ratio of true breeding tall pea plants to true breeding dwarf pea plants shall be
(1) 2:1
(2) 1:1
(3) 3:1
(4) 1:2
✅ (2) 1:1
13. “Gametes are never hybrid”. It is a statement of law of
(1) Dominance
(2) Random fertilization
(3) Independent assortment
(4) Segregation
✅ (4) Segregation
14. According to the Law of independent assortment, in a dihybrid cross
(1) There are 4 genotypes in F2
(2) F2 contains 16 phenotypes
(3) There is a single individual which is homozygous recessive for both the characters
(4) It is not possible to forecast the different phenotypes
✅ (3) There is a single individual which is homozygous recessive for both the characters
15. How many types of gametes will be produced by individuals of AABbcc genotype?
(1) 2
(2) 4
(3) 6
(4) 9
✅ (1) 2
16. The Mendelian principle which has always stood true is
(1) Law of independent assortment
(2) Law of segregation
(3) Law of dominance
(4) All the above
✅ (2) Law of segregation
17. Alleles of a gene are found on
(1) Same chromosome
(2) Homologous chromosomes
(3) Non-homologous chromosomes
(4) Any chromosomes
✅ (2) Homologous chromosomes
18. Crossing of an organism with dominant phenotype to a recessive individual is called
(1) Test cross
(2) Back cross
(3) Reciprocal cross
(4) Dihybrid cross
✅ (1) Test cross
19. A heterozygous round seeded plant is crossed to recessive wrinkled seeded plant. The progeny would be
(1) 303 rounded: 301 wrinkled
(2) 301 rounded: 100 wrinkled
(3) 20 rounded: 99 wrinkled
(4) 99 rounded: 301 wrinkled
✅ (1) 303 rounded: 301 wrinkled
20. Test cross ratio in a dihybrid cross would be
(1) 1:1
(2) 1:2:1
(3) 1:1:1:1
(4) 9:3:3:1
✅ (3) 1:1:1:1
21. A pure tall plant is reared in a soil poor in nutrition and reached the size of dwarf plant. If this plant is selfed, the phenotype in F1 generation is likely to be
(1) All tall plants
(2) 50% tall and 50% dwarf
(3) All dwarf
(4) Data insufficient
✅ (1) All tall plants
22. What should be the composition of gametes?
(1) GgLl
(2) Ggl
(3) Gg
(4) Gl
✅ (4) Gl
23. Percentage of heterozygous individuals obtained from selfing of Rr individual is
(1) 100
(2) 75
(3) 50
(4) 25
✅ (3) 50
24. In rabbits, the gene for grey fur (G) is dominant over that for black fur (g). In a litter, if 50% rabbits are grey, then the possible parental cross combination is
(1) GG X Gg
(2) GG X GG
(3) gg x gg
(4) Gg x gg
✅ (4) Gg x gg
25. In a population, a multiple allelic gene contains 5 alleles. Then the number of possible genotypes in that population would be
(1) 5
(2) 15
(3) 10
(4) 18
✅ (2) 15
26. Out of a population of 800 individuals in F2 generation of a cross between yellow round & green wrinkled pea plants, what would be number of yellow and wrinkled seeds?
(1) 800
(2) 400
(3) 200
(4) 150
✅ (4) 150
Topic 2: OTHER PATTERNS OF INHERITANCE
NEET: Previous Years Questions
27. A pink flowered Snapdragon plant was crossed with a red flowered Snapdragon plant. What type of phenotype/s is/are expected in the progeny?
(1) Only red flowered plants
(2) Red flowered as well as pink flowered plants
(3) Only pink flowered plants
(4) Red, Pink as well as white flowered plants (NEET 2024)
✅ (2) Red flowered as well as pink flowered plants
28. As per ABO blood grouping system, the blood group of father is B+, mother is A+ and child is O+. Their respective genotype can be
A. IBi / IAi / ii
B. IBIB / IAIA / ii
C. IAIB / IAi / IBi
D. IAi /IBi / IAi
E. IBi / IAi /IAIB
Choose the most appropriate answer from the options given below:
(1) A only
(2) B only
(3) C & B only
(4) D & E only (NEET 2024)
✅ (1) A only
The phenomenon of pleiotropism refers to
(1) Presence of two alleles, each of the two genes controlling a single trait
(2) A single gene affecting multiple phenotypic expression
(3) More than two genes affecting a single character
(4) Presence of several alleles of a single gene controlling a single Crossover (NEET 2023)
✅ (2) A single gene affecting multiple phenotypic expression
30. Identify the wrong statement with reference to the gene ‘I’ that controls ABO blood groups. (NEET 2020)
(1) When IA and IB are present together, they express same type of sugar.
(2) Allele ‘i' does not produce any sugar.
(3) The gene (I) has three alleles.
(4) A person will have only two of the three alleles.
✅ (1) When IA and IB are present together, they express same type of sugar.
31. In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F1 generation, pink flowers were obtained. When pink flowers were selfed, the F2 generation showed white, red and pink flowers. Choose the incorrect statement from the following:
(1) This experiment does not follow the Principle of Dominance
(2) Pink colour in F1 is due to incomplete dominance
(3) Ratio of F2 is ¼ (Red): ²/₄ (Pink): ¼ (White)
(4) Law of Segregation does not apply in this experiment (NEET 2019)
✅ (1) This experiment does not follow the Principle of Dominance
32. Which of the following pairs is wrongly matched?
(1) Starch synthesis in pea: Multiple alleles
(2) ABO blood grouping: Co-dominance
(3) XO type sex determination: Grasshopper
(4) T.H Morgan: Linkage (NEET 2018)
✅ (1) Starch synthesis in pea: Multiple alleles
33. Which of the following characteristics represent ‘Inheritance of Blood groups’ in humans?
i. Dominance
ii. Co-dominance
iii.Multiple allele
iv. Incomplete dominance
v. Polygenic inheritance
(1) ii, iii and v
(2) i, ii and iii
(3) ii, iv and v
(4) i, iii and v (NEET 2018)
✅ (2) i, ii and iii
34. The genotypes of a husband and wife are IAIB and IAi. Among the blood types of their children, how many different genotypes and phenotypes are possible?
(1) 3 genotypes; 4 phenotypes
(2) 4 genotypes; 3 phenotypes
(3) 4 genotypes; 4 phenotypes
(4) 3 genotypes; 3 phenotypes (NEET 2017)
✅ (2) 4 genotypes; 3 phenotypes
35. Match the terms in column I with their description in column II and choose the correct option. (NEET-I 2016)
✅ (4) (ii) (iii) (iv) (i)
Model Questions
36. Two pink flowered snap dragon plants (Rr) are self-pollinated. The probability of the offspring to have white flowers are
(1) 25%
(2) 50%
(3) 75%
(4) 0%
✅ (1) 25%
37. A blue fowl obtained from mating between black and white fowls, is self-crossed. The F2 ratio is
(1) 1 black: 2 white: 1 blue
(2) 2 black: 1 white: 1 blue
(3) 1 black: 2 blue: 1 white
(4) 1 black: 1 white: 1 blue
✅ (3) 1 black: 2 blue: 1 white
38. ABO blood grouping shows
(1) Co-dominant genes
(2) Polygenes
(3) Dominant-recessive genes
(4) Both co-dominant & dominant recessive genes
✅ (4) Both co-dominant & dominant recessive genes
39. A child of blood group O cannot have parents of blood groups
(1) AB and AB/O
(2) A and B
(3) B and B
(4) O and O
✅ (1) AB and AB/O
40. Four children belonging to same parents have the blood groups A, B, AB & O. The genotypes of the parents are
(1) Both parents are homozygous for A group
(2) One parent is homozygous for A and another parent is homozygous for B
(3) One parent is heterozygous for A and another parent is heterozygous for B
(4) Both parents are homozygous for B group
✅ (3) One parent is heterozygous for A and another parent is heterozygous for B
41. In ABO system, blood group genes show multiple allelism. They include
(1) One dominant allele and 2 recessive alleles
(2) Two dominant alleles and 2 recessive alleles
(3) One dominant allele and 3 recessive alleles
(4) Two dominant alleles and one recessive allele
✅ (4) Two dominant alleles and one recessive allele
42. Multiple phenotype is seen in
(1) Multiple gene inheritance
(2) Pleiotropy
(3) Multiple allelism
(4) Co-dominance
✅ (2) Pleiotropy
43. Which of the following is an example for Pleiotropy?
(1) Starch synthesis in pea
(2) Phenylketonuria
(3) Sickle cell anaemia
(4) All of these
✅ (4) All of these
44. Inheritance of human skin colour and human height is
(1) Mendelian inheritance
(2) Monogenic inheritance
(3) Complementary genes
(4) Polygenic inheritance
✅ (4) Polygenic inheritance
45. Which of the following category of genotypes represent intermediate (mulatto) skin colour in human?
(1) AABBCC, AaBbCc, aabbcc, AabbCC
(2) AaBBCC, Aabbcc, aabbcc, AabbCc
(3) AaBbCc, aaBBCc, AabbCC, AABbcc
(4) aaBBCC, AaBbCc, aabbcc, aabbCC
✅ (3) AaBbCc, aaBBCc, AabbCC, AABbcc
Topic 3: CHROMOSOMAL THEORY, LINKAGE & RECOMBINATION
NEET: Previous Years Questions
46. Frequency of recombination between gene pairs on same chromosome as a measure of the distance between genes to map their position on chromosome, was used for the first time by
(1) Sutton and Boveri
(2) Alfred Sturtevant
(3) Henking
(4) Thomas Hunt Morgan (NEET 2023)
✅ (2) Alfred Sturtevant
47. Experimental verification of the chromosomal theory of inheritance was done by
(1) Boveri
(2) Morgan
(3) Mendel
(4) Sutton (NEET 2020)
✅ (2) Morgan
48. The frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes was explained by:
(1) T.H. Morgan
(2) Gregor J. Mendel
(3) Alfred Sturtevant
(4) Sutton & Boveri (NEET 2019)
✅ (3) Alfred Sturtevant
49. What map unit (Centimorgan) is adopted in the construction of genetic maps?
(1) A unit of distance between two expressed genes, representing 10% cross over
(2) A unit of distance between two expressed genes, representing 100% cross over
(3) A unit of distance between genes on chromosomes, representing 1% cross over
(4) A unit of distance between genes on chromosomes, representing 50% cross over (NEET 2019)
✅ (3) A unit of distance between genes on chromosomes, representing 1% cross over
50. Select the incorrect statement.
(1) Male fruit fly is heterogametic.
(2) In male grasshoppers, 50% of sperms have no sex-chromosome.
(3) In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
(4) Human males have one of their sex-chromosome much shorter than the other. (NEET 2019)
✅ (3) In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
51. The mechanism that causes a gene to move from one linkage group to another is called
(1) inversion
(2) duplication
(3) translocation
(4) crossing-over (NEET-II 2016)
✅ (3) translocation
52. In a test cross involving F1 dihybrid flies, more parental-type offspring were produced than the recombinant-type offspring. This indicates
(1) the two genes are linked and present on the same chromosome
(2) both of the characters are controlled by more than one gene
(3) the two genes are located on two different chromosomes
(4) chromosomes failed to separate during meiosis. (NEET-I 2016)
✅ (1) the two genes are linked and present on the same chromosome
Model Questions
53. Who proposed Chromosomal theory of inheritance?
(1) Walter Sutton and Theodore Boveri
(2) de Vries, Correns & von Tschermak
(3) Thomas Hunt Morgan
(4) Alfred Sturtevant
✅ (1) Walter Sutton and Theodore Boveri
54. Morgan selected Drosophila for genetic study because
(1) Short life cycle of 2 weeks
(2) Numerous offspring in each mating
(3) Inexpensive to breed
(4) All of these
✅ (4) All of these
55. Regarding Morgan’s study in Drosophila, which is false?
(1) Genes of eye colour, body colour and wing size were located on the X chromosome
(2) Genes of white eye & yellow body are tightly linked
(3) Genes of white eye & small wing are loosely linked
(4) Loosely linked genes show low recombination
✅ (4) Loosely linked genes show low recombination
56. Mendelian recombination is due to
(1) Linkage
(2) Crossing over
(3) Mutations
(4) Independent assortment
✅ (4) Independent assortment
57. Genes P & Q are both required in dominant state for normal hearing. A deaf couple has all children with normal hearing. The probable genotype for the couple is
(1) PPqq x ppQQ
(2) PPqq x PPqq
(3) PpQq x ppqq
(4) PPqq x ppQq
✅ (1) PPqq x ppQQ
58. What is correct about linked genes?
(1) Segregation occurs but no dominance
(2) No segregation but independent assortment
(3) No segregation, no dominance
(4) Segregation but no independent assortment
✅ (4) Segregation but no independent assortment
59. Percentage of recombination between a & b is 9%, a & c 17% and b & c is 26%. The arrangement of genes is
(1) a-b-c
(2) a-c-b
(3) b-c-a
(4) b-a-c
✅ (4) b-a-c
Topic 4: SEX DETERMINATION
Model Questions
60. The nuclear structure observed by Henking in 50% of the insect sperm after spermatogenesis was
(1) Polar body
(2) X body
(3) Y chromosome
(4) Nucleolus
✅ (2) X body
61. Which one of the following conditions correctly describes the manner of determining the sex in the given example?
(1) XO type of sex chromosomes determine the male sex in grasshopper
(2) XO condition in humans as found in Turner’s syndrome, determine female sex
(3) Homozygous sex chromosomes (XX) produce male in Drosophila
(4) Homozygous sex chromosomes (ZZ) determine female sex in birds
✅ (1) XO type of sex chromosomes determine the male sex in grasshopper
62. When released from ovary, human egg contains
(1) One Y Chromosome
(2) 2 X chromosomes
(3) One X Chromosome
(4) XY chromosome
✅ (3) One X Chromosome
sex determination of birds
(1) Male is homogametic (ZZ) and female is heterogametic (Z & W)
(2) Male is heterogametic (Z & W) and female is homogametic (ZZ)
(3) Male is homogametic (XX) and female is heterogametic (XO)
(4) Male is heterogametic (XO) and female is homogametic (XX)
✅ (1) Male is homogametic (ZZ) and female is heterogametic (Z & W)
64. XX-XY sex determination mechanism is found in
(1) Human, Drosophila and Grasshopper
(2) Chimpanzee, Drosophila and Human
(3) Birds, Drosophila and Grasshopper
(4) Human, Periplaneta and Grasshopper
✅ (2) Chimpanzee, Drosophila and Human
65. Which is wrong about sex determination in honeybee?
(1) Sex determination in honeybee is called as haplodiploid sex determination system.
(2) Fertilised egg develops as queen or worker.
(3) Drones are developed by parthenogenesis.
(4) Males are diploid and females are haploid.
✅ (4) Males are diploid and females are haploid.
Topic 5: MUTATION, PEDIGREE ANALYSIS AND GENETIC DISORDERS
NEET: Previous Years Questions
66. Match List I with List II. (NEET 2024)
Choose the correct answer from the options given below:
(1) A-I, B-II, C-III, D-IV
(2) A-II, B-III, C-IV, D-I
(3) A-III, B-IV, C-I, D-II
(4) A-IV, B-I, C-II, D-III
✅ (3) A-III, B-IV, C-I, D-II
67. Which one of the following symbols represents mating between relatives in human pedigree analysis? (NEET 2023)
✅ (1)
68. Which of the following statements are correct about Klinefelter’s syndrome?
A. This disorder was first described by Langdon Down (1866).
B. Such an individual has overall masculine development. However, the feminine development is also expressed.
C. The affected individual is short statured.
D. Physical, psychomotor and metal development is retarded.
E. Such individuals are sterile.
Choose the correct answer from the options given below:
(1) C and D only
(2) B and E only
(3) A and E only
(4) A and B only (NEET 2023)
✅ (2) B and E only
69. Broad palm with single palm crease is visible in a person suffering from
(1) Turner’s syndrome
(2) Klinefelter’s syndrome
(3) Thalassemia
(4) Down’s syndrome (NEET 2023)
✅ (4) Down’s syndrome
70. In a cross between a male and female, both heterozygous for sickle cell anaemia gene, what percentage of the progeny will be diseased?
(1) 50%
(2) 75%
(3) 25%
(4) 100% (NEET 2021)
✅ (3) 25%
71. Select the correct match. (NEET 2020)
(1) Sickle cell anaemia - Autosomal recessive trait, chromosome-11
(2) Thalassemia - X linked
(3) Haemophilia - Y linked
(4) Phenylketonuria - Autosomal dominant trait
✅ (1) Sickle cell anaemia - Autosomal recessive trait, chromosome-11
72. Which of the following muscular disorders is inherited?
(1) Tetany
(2) Muscular dystrophy
(3) Myasthenia gravis
(4) Botulism (NEET 2019)
✅ (2) Muscular dystrophy
73. What is the genetic disorder in which an individual has an overall masculine development, Gynaecomastia, and is sterile?
(1) Turner's syndrome
(2) Klinefelter's syndrome
(3) Edward syndrome
(4) Down's syndrome (NEET 2019)
✅ (2) Klinefelter's syndrome
74. A woman has an X-linked condition on one of her X chromosomes. This chromosome can be inherited by
(1) Only daughters
(2) Only sons
(3) Only grandchildren
(4) Both sons and daughter (NEET 2018)
✅ (4) Both sons and daughter
75. Thalassemia and sickle cell anaemia are caused due to a problem in globin molecule synthesis. Select the correct statement.
(1) Both are due to a quantitative defect in globin chain synthesis.
(2) Thalassemia is due to less synthesis of globin molecules.
(3) Sickle cell anaemia is due to a quantitative problem of globin molecules.
(4) Both are due to a qualitative defect in globin chain synthesis. (NEET 2017)
✅ (2) Thalassemia is due to less synthesis of globin molecules.
76. A disease caused by an autosomal primary nondisjunction is
(1) Klinefelter’s syndrome
(2) Turner’s syndrome
(3) Sickle cell anaemia
(4) Down’s syndrome (NEET 2017)
✅ (4) Down’s syndrome
77. If a colour-blind man marries a woman who is homozygous for normal colour vision, the probability of their son being colour-blind is
(1) 0
(2) 0.5
(3) 0.75
(4) 1 (NEET-II 2016)
✅ (1) 0
78. Pick out the correct statements.
i. Haemophilia is a sex-linked recessive disease.
ii. Down’s syndrome is due to aneuploidy.
iii. Phenylketonuria is an autosomal recessive gene disorder.
iv. Sickle cell anaemia is an X-linked recessive gene disorder.
(1) i, iii and iv are correct.
(2) i, ii and iii are correct.
(3) i and iv are correct.
(4) ii and iv are correct. (NEET-I 2016)
✅ (2) i, ii and iii are correct.
79. Which of the following most appropriately describes haemophilia?
(1) Chromosomal disorder
(2) Dominant gene disorder
(3) Recessive gene disorder
(4) X-linked recessive gene disorder (NEET-I 2016)
✅ (4) X-linked recessive gene disorder
Model Questions
80. When a mutation is limited to the substitution of one nucleotide for another, it is called
(1) Translocation
(2) Point mutation
(3) Base inversion
(4) Frame shift mutation
✅ (2) Point mutation
81. Loss (deletion) or gain (insertion/ duplication) of DNA segment cause
(1) Chromosomal aberration which are not seen in cancer cells
(2) Chromosomal aberration which do not lead to frameshift mutation
(3) Frame shift mutation which is not present in cancer cells
(4) Frame shift mutation which is present in cancer cells
✅ (4) Frame shift mutation which is present in cancer cells
82. In pedigree analysis, the symbol 
gives which of the following information?
gives which of the following information?
(1) It is the mating between relatives and male is not affected
(2) It is the mating between relatives and female is not affected
(3) Male is homozygous affected and female is recessive
(4) Male is heterozygous normal and female is homozygous normal
✅ (2) It is the mating between relatives and female is not affected
83. Which one of the patterns of inheritance is consistent with this pedigree?
(1) Autosomal recessive
(2) Autosomal dominant
(3) Y-linkage
(4) Sex-linked recessive
✅ (3) Y-linkage
84. Haemophiliac man marries a carrier woman. % of daughters becoming haemophiliac shall be
(1) 0%
(2) 50%
(3) 75%
(4) 100%
✅ (2) 50%
85. In sickle cell anaemia, the glutamic acid is replaced by
(1) Proline
(2) Alanine
(3) Serine
(4) Valine
✅ (4) Valine
86. Sickle cell anaemia is due to
(1) Mutation of CTC to CAC on gene in chro. 11
(2) Change of GAG to GUG on the mRNA
(3) Change of GUG to GAG on the mRNA
(4) Both A & B
✅ (4) Both A & B
87. Both husband and wife have normal vision though their fathers were colourblind. The probability of their daughter becoming colourblind is
(1) 0%
(2) 25%
(3) 50%
(4) 75%
✅ (1) 0%
88. Male child with blood group AB is colourblind. His parents could be
(1) Father normal vision with blood group A, mother colourblind with group O
(2) Father colourblind with group O, mother colourblind with group AB
(3) Father normal vision with blood group A, mother colourblind with group B
(4) Father colourblind with group O, mother normal vision with group O
✅ (3) Father normal vision with blood group A, mother colourblind with group B
89. Albinism and phenylketonuria are disorders due to
(1) Recessive Autosomal genes
(2) Dominant Autosomal genes
(3) Dominant sex genes
(4) Recessive sex genes
✅ (1) Recessive Autosomal genes
90. Which is not true about Phenylketonuria?
(1) It causes mental retardation
(2) Phenyl alanine hydroxylase absent
(3) Phenylalanine is converted to tyrosine
(4) Phenyl pyruvic acid is excreted through urine
✅ (3) Phenylalanine is converted to tyrosine
91. α Thalassemia is due to the mutation of
(1) HBA1 & HBA2 genes on chromosome 16
(2) HBB gene on chromosome 11
(3) HBB gene on chromosome 16
(4) HbA gene on chromosome 11 into HbS
✅ (1) HBA1 & HBA2 genes on chromosome 16
92. Regarding Sickle cell anaemia and Thalassaemia, select the true statement.
(1) Both are sex-linked recessive blood diseases.
(2) Both are quantitative problems of synthesis of few globin molecules.
(3) Beta thalassemia is controlled by two closely linked genes HBA1 & HBA2 on chromosome 16.
(4) Both are transmitted from unaffected carrier (heterozygous) parents to the offspring.
✅ (4) Both are transmitted from unaffected carrier (heterozygous) parents to the offspring.
93. Marriage between close relatives should be avoided because it induces more
(1) Recessive alleles to come together
(2) Mutations
(3) Multiple births
(4) Blood group abnormalities
✅ (1) Recessive alleles to come together
94. Haploid chromosome number is 12. What is the number in a Monosomic?
(1) 23
(2) 22
(3) 25
(4) 26
✅ (1) 23
95. Which one is not a feature of Down’s syndrome?
(1) Broad flat face
(2) Furrowed big tongue
(3) Gynaecomastia
(4) Partially open mouth
✅ (3) Gynaecomastia
96. Ovum producing Klinefelter’s syndrome shall have chromosome number
(1) 21
(2) 22
(3) 23
(4) 24
✅ (4) 24
97. The chromosomal condition in Turner’s syndrome is
(1) 21 trisomy + XY
(2) 44 autosomes + XXY
(3) 44 autosomes + XYY
(4) 44 autosomes + XO
✅ (4) 44 autosomes + XO
98. Which one of the following is responsible for mental abnormalities in humans?
(1) XXX and XY
(2) XX and XXX
(3) XO and XXX
(4) XX and XO
✅ (3) XO and XXX