Principles of Inheritance and Variation
Previous year questions with solutions · 2000 – 2026
168 Questions
34 Papers covered
8.91% ↑60.4% Weightage in 2026
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Year-wise statistics questions · papers · average per paper · weightage Year Questions Papers Avg / paper Weightage 2026 9 2 4.5 8.91% ↑60.4% 2025 3 1 3 5.56% ↓47.2% 2024 12 2 6 10.53% ↑32.6% 2023 5 1 5 7.94% ↓13.4% 2022 12 2 6 9.16% ↑174.8% 2021 2 1 2 3.33% ↓58.3% 2020 4 1 4 8.00% ↓15.2% 2019 5 1 5 9.43% ↑29.7% 2018 4 1 4 7.27% ↓17.1% 2017 5 1 5 8.77% ↑12.1% 2016 9 2 4.5 7.83% ↑42.2% 2015 6 2 3 5.50% ↓23.6% 2013 8 2 4 7.21% ↑48.5% 2012 5 2 2.5 4.85% ↑16.5% 2011 4 2 2 4.17% ↓58.3% 2010 9 2 4.5 10.00% ↑40% 2009 4 1 4 7.14% ↑96.4% 2008 2 1 2 3.64% ↓62.9% 2007 5 1 5 9.80% ↓35.7% 2006 9 1 9 15.25% ↑20.1% 2005 8 1 8 12.70% ↓12.7% 2004 8 1 8 14.55% ↑12.7% 2003 8 1 8 12.90% ↑3.2% 2002 8 1 8 12.50% ↓18.1% 2001 9 1 9 15.25% ↑64.7% 2000 5 1 5 9.26%
All 168 MCQ 163 Matching 5
TopicAll Chromosomal Theory of Inheritance, Linkage and Recombination Dihybrid Cross and Law of Independent Assortment Genetic Disorders: Chromosomal (Down's, Klinefelter's, Turner's) Genetic Disorders: Mendelian (Haemophilia, Colour Blindness, Sickle Cell, PKU, Thalassemia) Incomplete Dominance, Co-dominance and Multiple Allelism (ABO Blood Groups) Mendel's Laws of Inheritance, Monohybrid Cross Mutation Pedigree Analysis Polygenic Inheritance and Pleiotropy Sex Determination (Humans, Birds, Honey Bee, Grasshopper) YearAll 2026 2025 2024 2023 2022 2021 2020 2019 2018 2017 2016 2015 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000
⚠ 1 of these questions are out of the current syllabus (marked on the question).
31
Given below are two statements: In the light of the above statements, choose the correct answer from the options given below :
Both Statement I and Statement II are correct Both Statement I and Statement II are incorrect Statement I is correct but Statement II is incorrect Statement I is incorrect but Statement II is correct
NEET (UG) 2022
32
Which of the following occurs due to the presence of autosome linked dominant trait?
Sickle cell anaemia Myotonic dystrophy Haemophilia Thalassemia
NEET (UG) 2022
33
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the correct answer from the options given below :
Both (A) and (R) are correct and (R) is the correct explanation of (A) Both (A) and (R) are correct but (R) is not the correct explanation of (A) (A) is correct but (R) is not correct (A) is not correct but (R) is correct
NEET (UG) 2022
34
If a colour blind female marries a man whose mother was also colour blind, what are the chances of her progeny having colour blindness?
25% 50% 75% 100%
NEET (UG) 2022
35
The recombination frequency between the genes a & c is 5%, b & c is 15%, b & d is 9%, a & b is 20%, c & d is 24% and a & d is 29%. What will be the sequence of these genes on a linear chromosome?
a, d, b, c d, b, a, c a, b, c, d a, c, b, d
NEET (UG) 2022
36
Given below are two statements: In the light of the above statements, choose the correct answer from the options given below :
Statement I is incorrect but Statement II is correct Both Statement I and Statement II are correct Both Statement I and Statement II are incorrect Statement I is correct but Statement II is incorrect
NEET (UG) 2022 (Phase 2)
37
The chromosomal theory of inheritance was proposed by
Robert Brown Thomas Morgan Sutton and Boveri Gregor Mendel
NEET (UG) 2022 (Phase 2)
38
What is the expected percentage of F2 progeny with yellow and inflated pod in dihybrid cross experiment involving pea plants with green coloured, inflated pod and yellow coloured constricted pod?
9% 100% 56.25% 18.75%
NEET (UG) 2022 (Phase 2)
39
If a female individual is with small round head, furrowed tongue, partially open mouth and broad palm with characteristic palm crease. Also the physical, psychomotor and mental development is retarded. The karyotype analysis of such an individual will show :
Trisomy of chromosome 21 47 chromosomes with XXY sex chromosomes 45 chromosomes with XO sex chromosomes 47 chromosomes with XYY sex chromosomes
NEET (UG) 2022 (Phase 2)
40
Select the incorrect match regarding the symbols used in the Pedigree analysis:
[figure] – Parent with male child affected with disease [figure] – Sex unspecified [figure] – Affected individual [figure] – Consanguineous mating
NEET (UG) 2022 (Phase 2)
41
A normal girl, whose mother is haemophilic marries a male with no ancestral history of haemophilia. What will be the possible phenotypes of the offspring? Choose the most appropriate answer from the options given below:
B and D only A and B only B and C only A and D only
NEET (UG) 2022 (Phase 2)
42
The production of gametes by the parents, formation of zygotes, the F1 and F2 plants, can be understood from a diagram called :
Net square Bullet square Punch square Punnett square
NEET (UG) 2021
43
In a cross between a male and female, both heterozygous for sickle cell anaemia gene, what percentage of the progeny will be diseased?
100% 50% 75% 25%
NEET (UG) 2021
44
Experimental verification of the chromosomal theory of inheritance was done by
Sutton Mendel Morgan Boveri
NEET (UG) 2020
45
Select the correct match
Thalassemia – X linked Sickle cell anaemia – Autosomal recessive trait, chromosome-11 Phenylketonuria – Autosomal dominant trait Haemophilia – Y linked
NEET (UG) 2020
46
Identify the wrong statement with reference to the gene ‘I’ that controls ABO blood groups.
Allele ‘i’ does not produce any sugar. The gene (I) has three alleles. When IA and IB are present together, they express same type of sugar. A person will have only two of the three alleles.
NEET (UG) 2020
47
How many true breeding pea plant varieties did Mendel select as pairs, which were similar except in one character with contrasting traits?
14 4 2 8
NEET (UG) 2020
48
The frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes was explained by :
Alfred Sturtevant Gregor J. Mendel Sutton Boveri T.H. Morgan
NEET (UG) 2019
49
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 :
Ratio of F2 is 14 (Red) : 24 (Pink) : 14 (White) Law of Segregation does not apply in this experiment This experiment does not follow the Principle of Dominance Pink colour in F1 is due to incomplete dominance
NEET (UG) 2019
50
What map unit (Centimorgan) is adopted in the construction of genetic maps?
A unit of distance between genes on chromosomes, representing 1\% cross over. A unit of distance between genes on chromosomes, representing 50\% cross over. A unit of distance between two expressed genes, representing 10\% cross over. A unit of distance between two expressed genes, representing 100\% cross over.
NEET (UG) 2019
51
What is the genetic disorder in which an individual has an overall masculine development, gynaecomastia, and is sterile?
Edward syndrome Down’s syndrome Turner’s syndrome Klinefelter’s syndrome
NEET (UG) 2019
52
Select the incorrect statement.
In domesticated fowls, sex of progeny depends on the type of sperm rather than egg. Human males have one of their sex-chromosome much shorter than the other. Male fruit fly is heterogametic In male grasshoppers, 50\% of sperms have no sex-chromosome.
NEET (UG) 2019
53
Which of the following pairs is wrongly matched?
Starch synthesis in pea : Multiple alleles ABO blood grouping : Co-dominance XO type sex determination: Grasshopper T.H. Morgan : Linkage
NEET 2018
54
Which of the following characteristics represent 'Inheritance of blood groups' in humans?
B, C and E only A, B and C only B, D and E only A, C and E only
NEET 2018
55
A woman has an X-linked condition on one of her X chromosomes. This chromosome can be inherited by
only daughters only sons only grandchildren both sons and daughters
NEET 2018
56
Select the correct statement :
Franklin Stahl coined the term “linkage”. Punnett square was developed by a British scientist. Spliceosomes take part in translation. Transduction was discovered by S. Altman.
NEET 2018
57
Thalassemia and sickle cell anemia are caused due to a problem in globin molecule synthesis. Select the correct statement.
Both are due to a qualitative defect in globin chain synthesis Thalassemia is due to less synthesis of globin molecules Sickle cell anemia is due to a quantitative problem of globin molecules Both are due to a quantitative defect in globin chain synthesis
NEET 2017
58
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?
4 genotypes ; 3 phenotypes 4 genotypes ; 4 phenotypes 3 genotypes ; 4 phenotypes 3 genotypes ; 3 phenotypes
NEET 2017
59
A disease caused by an autosomal primary non-disjunction is :
Klinefelter's Syndrome Down's Syndrome Turner's Syndrome Sickle Cell Anemia
NEET 2017
60
Which one from those given below is the period for Mendel's hybridisation experiments ?
1870 – 1877 1857 – 1869 1840 – 1850 1856 – 1863
NEET 2017