Principles of Inheritance and variation Mcqs For Neet Examination 2021-22.

Get the Multiple Choice questions and previous year question of Principles of Inheritance and variation for Neet Examination.

Subtopics of Principles of Inheritance and variation

1. Mendel's Laws of Inheritance.

2. Sex Determination.

3. Deviation from Mendelism.

4. Genetic Disorders.

5. Chromosomal Theory of Inheritance, Linkage and Recombination.

Download the Pdf of Principles of Inheritance and variation Question from Past Year of Neet examination.


1. haploids are able to express both recessive and dominant alleles/mutations because there are

(A) many alleles for each gene
(B) two alleles for each gene
(C) only one allele for each gene in the individual
(D) only one allele in a gene 

2. segregation of mendelian factor (Aa) occurs during

(A) diplotene
(B) anaphase I
(C) zygotene/pachytene
(D) anaphase II

3. tt mates with Tt. What will be characteristic of offspring?

(A) 75% recessive
(B) 50% recessive
(C) 25% recessive
(D) all dominant 

4. cross between AaBB and aaBB will form

(A) 1AaBB : 1aaBB
(B) all AaBB
(C) 3AaBB : 1aaBB
(D) 1AaBB : 3aaBB 

5. In meiosis, the daughter cells differ from parent cell as well as amongst themselves due to

(A) segregation, independent assortment and crossing over
(B) segregation and crossing over
(C) independent assortment and crossing over
(D) segregation and independent assortment 

6. The allele which is unable to express its effect in the presence of other is called

(A) codominant
(B) supplementary
(C) complementary
(D) recessive 

7. Blue eye colour is recessive to brown eye colour. A brown eyed man whose mother was blue eyed marries a blue-eyed woman. the children will be 

(A) both blue eyed and brown eyed 1 : 1
(B) all brown eyed
(C) all blue eyed
(D) blue eyed and brown eyed 3 : 1

8. Mendle's last law is

(A) segregation
(B) dominance
(C) independent assortment
(D) polygenic inheritance

9. First geneticist/father of genetics was

(A) De vries
(B) mendel
(C) Darwin
(D) morgan

10. The contrasting pairs of factors in mendelian crosses are called

(A) multiple alleles
(B) allelomorphs
(C) alloloci
(D) paramorphs

11. An organism with two identical alleles is

(A) dominant
(B) hybird
(C) heterozygous
(D) homozygous

12. In a cross between AABB aabb, the ratio oh F² genotypes between AABB, AaBB, Aabb and aabb would be

(A) 9 : 3 : 3 : 1
(B) 2 : 1 : 1 : 2
(C) 1 : 2 : 2 : 1
(D) 7 : 5 : 3 : 1

13. An allele is dominant if it is expressed in

(A) both homozygous and heterozygous states
(B) second generation
(C) heterozygous combination
(D) homozygous combination

14. Mendel studied inheritance of seven pairs of traits in pea which can have 21 possible
combinations. Independent assortment is not observed in later studies, your reaction will be

(A) Independent assortment principle may be wrong
(B) mendel might not have studied all the combinations
(C) it is impossible
(D) later studies may be wrong

15. How many different types of genetically different gametes will be produced by a
heterozygous plant having the genotype AABbCc?

(A) six
(B) nine
(C) two
(D) four

16. If mendel had studied the seven traits using a plant with 12 chromosomes instead of 14, in
what way would his interpretation have been different?

(A) he would not have discovered the law of independent assortment
(B) he would have discovered sex linkage
(C) he could have mapped the chromosome
(D) he would have discovered blending or incomplete dominance

17. In hybridization, Tt tt gives rise to the progeny of ratio

(A) 2 : 1
(B) 1 : 2 : 1
(C) 1 : 1
(D) 1 : 2

18. According to mendelism, which character shows dominance?

(A) terminal position of flower
(B) green colour in seed coat
(C) wrinkled seeds
(D) green pod colour

19. Due to the cross between TTRr ttrr the resultant progenoes show what percent of tall, red
flowered plants

(A) 50%
(B) 75%
(C) 25%
(D) 100%

20. A and B genes are linked. What shall be genotype of progeny in a cross between AB/ab and

(A) AAbb and aabb
(B) AaBb and aabb
(C) AABB and aabb
(D) none of the above

21. a gene is said to be dominant if

(A) it expresses its effect only in homozygous state
(B) it expresses its effect only in heterozygous condition
(C) it expresses its effect both in homozygous and heterozygous condition
(D) it never expresses its effect in any condition

22. Two crosses between the same pair of genotypes or phenotypes in which the sources of the
gametes are reversed in one cross, is known as

(A) text cross
(B) reciprocal cross
(C) dihybrid cross
(D) reverse cross

23. 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

24. In a plant, red fruit (R) is dominant over yellow fruit (r) and tallness (T) is dominant over
shortness (t). If a plant with RRTt genotype crossed with a plant that is rrtt,

(A) 25% will be tall with red fruit
(B) 50% will be tall with ref fruit
(C) 75% will be tall with red fruit
(D) all the offspring will be tall with red fruit

25. In order to find out the different types of gamets produced by a pea plant having the
genotype AaBb it should be crossed to a plant with the genotype

(B) AaBb
(C) aabb
(D) aaBB

26. Phenotype of an organism is the result of

(A) genotype and environment interactions
(B) mutations and linkages
(C) cytoplasmic effect and nutrition
(D) environmental changes and sexual dimorphism

27. How many different kinds of gamets will be produced by a plant having the genotype

(A) two
(B) three
(C) four
(D) nine

28. In Mendel's experiments with garden pea, round seed shape (RR) was dominant over
wrinkled seeds (rr), yellow cotyledon (YY). What are the expected phenotypes in the F²
generation of the cross RRYY rryy?

(A) round seeds with yellow cotyledons, and wrinkled seeds with yellow cotyledons
(B) only round seeds with green cotyledons
(C) only wrinkled seeds with yellow cotyledons
(D) only wrinkled seeds with green cotyledons

29. Test cross involves crossing

(A) between two genotypes with recessive trait
(B) between two F¹ hybrids
(C) the F¹ hybrid with a double recessive genotype
(D) between two genotypes with dominant trait

30. In pea plants, yellow seeds are dominant to green. If a heterozygous yellow seeded plant is
crossed with a green seeded plant, what ratio of yellow and green seeded plants would youexpect in F¹ generation?

(A) 9 : 1
(B) 1 : 3
(C) 3 : 1
(D) 50 : 50