Principles Of Inheritance And Variation MCQs – NEET Biology

Principles Of Inheritance And Variation MCQs

Question 1. Epistasis was discovered by :

1. Johanssen
2. Shull
3. Bateson
4. Mendel.

Answer: 3. Bateson

Question 2. In an experiment on pea plants, plants with round yellow seeds were crossed with wrinkled green seeds. What will be the phenotypic ratio of F₂ progeny?

1. All round yellow
2. 9 round yellow, 3 round green, 3 wrinkled yellow, 1 wrinkled green
3. 1 round yellow, 1 round green. 1 wrinkled yellow, 1 wrinkled green
4. All wrinkled green.

Answer: 2. 9 round yellow, 3 round green, 3 wrinkled yellow, 1 wrinkled green

Question 3. Some people experience PTC paper on the tongue as bitter; others as tasteless. This character is hereditary. Suppose T stands for dominant gene and t stands for recessive gene, the genetic makeup of a person who cannot taste is:

1. TT
2. Tt
3. tt
4. None of these.

Answer: 3. tt

Question 4. Monogenetic traits give rise to :

1. Independent assortment of characters
2. Colourblindness in man
3. Mendelian segregation
4. Incomplete dominance.

Answer: 3. Mendelian segregation

Question 5. From a cross AABB x aaBB, the following genotypic ratio will be obtained in F₁ generation:

1. 1 Aa BB : 3 aa BB
2. 3 Aa BB: 1 aa BB
3. All AABB: No aa BB
4. All AaBB.

Answer: 4. All AaBB.

Question 6. Due to incomplete dominance, a cross between blue and white Andalusian Fowls results in:

1. 50% blue and 50% black fowls
2. 25% black and 75% white fowls
3. 50% blue and 50% white fowls
4. 25% blue and 75% white fowls.

Answer: 3. 50% blue and 50% white fowls

Question 7. A dwarf pea plant was treated with gibberellic acid. It grew as tall as the pure tall pea plant. If this treated plant is crossed with a pure tall plant then the phenotypic ratio of F. is likely to be :

1. All tall
2. 50% tall: 50% dwarf
3. 75% tall: 25% dwarf
4. All dwarf.

Answer: 1. All tall

Question 8. A cross is made between the two organisms both of which have a genetic make-up of Bb for a particular trait, and two offspring are produced. The first offspring exhibit the dominant trait. What is the probability that the second offspring will exhibit the recessive trait?

1. 1/4
2. 100
3. 3/4
4. zero.

Answer: 1. 1/4

Question 9. Why did the lost cross progeny or yellow vs. black mice give 25% more offspring than those resulting from yellow vs. yellow mice

1. Due to lethal factors
2. Due to cumulative factors
3. Due to pseudoallelism
4. Due to incomplete dominance.

Answer: 1. Due to lethal factors

Question 10. Mendelian recombination is due to :

1. Linkage
2. Mollifications
3. Independent assortment of genes
4. Mutation.

Answer: 3. Independent assortment of genes

Question 11. The genes controlling seven traits in peas studied by Mendel were later found to lie located on the following number of chromosomes

1. 4
2. 7
3. 5
4. 6.

Answer: 2. 7

Question 12. Some people experience PTC paper on the tongue as bitter, and others as tasteless. This character is hereditary. Suppose T stands for dominant gene and l stands for recessive gene. Tyre genetic makeup of a  person who cannot taste is:

1. TT
2. Tt
3. tt
4. None of the above.

Answer: 3. tt

Question 13. One of Mendel’s pure strains of pea plants had green peas. How many different kinds of eggs could such a plant produce about pea colour?

1. 1
2. 2
3. 4
4. 8.

Answer: 1. 1

Question 14. If the frequency of a recessive phenotype in a stable population is 25% of the frequency of the dominant allele in that population :

1. 10%
2. 40%
3. 50%
4. 80%.

Answer: 3. 50%

Question 15. Coat colour in rabbits is an example of:

1. Multiple alleles
2. Epistatic gene
3. Lethal factor,
4. Pseudoalleles.

Answer: 1. Multiple alleles

Question 16. Height in man is influenced by the interaction of:

1. 10 or more pairs of genes
2. 20 or more pairs of genes
3. Less than 5 pairs of genes
4. More than 15 pairs of genes.

Answer:  3. Less than 5 pairs of genes

Question 17. Tallness (T) is dominant and dwarfness (t) is a recessive character. After crossing several Tt plants, a crop of 100 plants is obtained. Out of these 77 are tall and 23 are dwarf. What is the approximate number of hybrids?

1. 100
2. 54
3. 77
4. 23.

Answer: 2. 54

Question 18. In a gamete the gene of a special fruit is represented by :

1. Tt
2. TT
3. tT
4. tt.

Answer: 3. tT

Question 19. Which of the following forms represents a pair of contrasting characters?

1. Allele
2. Phenotype
3. Homozygous
4. Heterozygous.

Answer: 4. Heterozygous.

Question 20. The alleles for coloured seed coal are dominant over the limit of while seed coat when flowers of a plant with while seed coat (ss) are pollinated with coloured seed coat (Ss), the of colour of seed coat in developing seed would be :

1. White
2. Coloured
3. White and coloured in 1 :1 ratio
4. Mosaic.

Answer: 3. white and coloured in 1 :1 ratio

Question 21.When an albino plant is crossed with a normal green plant, all plants in the progeny arc albino because:

1. Plastids are inherited through maternal parents
2. Albinism is dominant over green character
3. Crossing results in structural change in green plastids
4. Green plants of male parents become mutants.

Answer: 1. Plastids are inherited through maternal parents

Question 22. Which one of the following is a test cross?

1. TT x It
2. Tt x Tt
3. TT x TT
4. Tt x tt.

Answer: 4. Tt x tt.

Question 23. The gene for the red colour is completely dominant. A plant with genotype Rr is selfed, then the genotype of offspring would be :

1. 3:1
2. 9: 3:3:1
3. 1:2:1
4. None of the above.

Answer: 3. 1:2:1

Question 24. An organism with two copies of the same allele is:

1. Homozygous for that trait
2. Homologous for the allele
3. Heterozygous for the trait
4. Heterozygous for the allele.

Answer: 1. Homozygous for that trait

Question 25. How many different kinds of gametes can an organism of genotype Xx, Yy, and Zz produce?

1. 2
2. 4
3. 8
4. 16.

Answer: 3. 8

Question 26. A man receives his X chromosomes from :

1. His mother only
2. His father only
3. Both his mother and father
4. Either his mother or his father.

Answer: 1. His mother only

Question 27. In Mendel’s dihybrid crosses, two pairs of factors (T/t) and (R/r) are located in the:

1. A pair of non-homologous chromosome
2. Pair of homologous chromosome
3. The two sex chromosomes
4. Two pairs of homologous chromosomes.

Answer: 4. Two pairs of homologous chromosomes.

Question 28. When two genetic loci produce identical phenotypes in cis as well as trans position, they are considered to be :

1. Pseudoalleles
2. The parts of the same gene
3. Multiple alleles
4. Different genes.

Answer: 1. Pseudoalleles

Question 29. The phenomenon in which an allele of one gene suppresses the activity of an allele of another gene is known as :

1. Dominance
2. Inactivation
3. Epistasis
4. Suppression.

Answer: 3. Epistasis

Question 30. Gamete contains which of the following :

1. Both alleles of a gene
2. Only one allele of a gene
3. All alleles of a gene
4. None of the above.

Answer: 2. Only one allele of a gene

Question 31. In the F₂ generation, the no of yellow feed ami given soeiK counted by Mendel was:

1. 300:10
2. 30:10
3. 6002:2001
4. 3:1.

Answer: 3. 6002:2001

Question 32, A black dog heterozygous for coat colour is crossed with a white bitch recessive homozygous. Progeny will show black-to-white offspring in the ratio of:

1. 3 :1
2. 1:1
3. All black
4. All white.

Answer: 2. 1:1

Question 33. Sickle cell anaemia is  an example of:

1. Genie trait
2. Multiple alleles
3. TO Monohybrid cross
4. None.

Answer: 4. None.

Question 34. Which condition of zygote is lethal:

1. Hb^AHb^A
2. Hb^AHb^A
3. Hb^SHb^S
4. Hb- Mb.

Answer: 3. Hb^SHb^S

Question 35. The frequency distribution curve of skin colour in men is:

1. Parabola
2. Bell-shaped
3. S-Shaped
4. Bar-shaped.

Answer: 2. Bell-shaped

Question 36. Blood group ‘O’ has :

1. One glycoprotein on RBC
2. Two glycoproteins on RBC
3. Both
4. None of the above.

Answer: 4. None of the above.

Question 37. According to Mendel, there are :

1. 14 traits or varieties in pea
2. 7 traits
3. 3 traits
4. Many.

Answer: 4. Many.

Question 38. The botanical name of Snapdragon is :

1. Lathyms odoratus
2. Majus
3. Antirrhinum
4. None of the above.

Answer: 3. Antirrhinum

Question 39. AB blood group is due to :

1. Epistasis
2. Interaction
3. Pedigree
4. Codominance.

Answer: 4. Codominance.

Question 40. Assume a cross between red and white flowered plants which produce pink :

1. This is an example of dominance
2. This is due to co-dominance
3. This is due to segregation
4. This is due to incomplete dominance.

Answer: 4. This is due to incomplete dominance.

Question 41. Allele is called :

1. A pair of chromosome
2. A pair of contrasting character
3. A pair of sex chromosome
4. None of these.

Answer: 2. A pair of contrasting character

Question 42. Autosomes are :

1. Sex chromosomes
2. Other than sex chromosomes
3. X-chromosome
4. Y-chromosome.

Answer: 2. Other than sex chromosomes

Question 43.When two tmielnled individuals or lines me Crossed, the performance of F. hybrid is superior to both its patents. This phenomenon is called:

1. Heterosis
2. Transformation
3. Splicing
4. Metamorphosis.

Answer: 1. Heterosis

Question 44. A heterozygous individual carrying a recessive sex-linked gene is called :

1. Carrier
2. Crossing-over
3. Transmitter
4. Albino.

Answer: 1. Carrier

Question 45. Pioneer of modern genetics is:

1. Mendel
2. Morgan
3. De-Vries
4. Punnet.

Answer: 1. Mendel

Question 46. Mendel selected pea plant for his experiments because it has :

1. Short life cycle
2. A large number of offspring
3. Sexual reproduction
4. All of these.

Answer: 2. Large number of offspring

Question 47. The ratio between tall and dwarf plants in F₁ generation is

1. 9 : 3 : 3: 1
2. 3: 1
3. 1 : 3 :3: 9
4. 7: 1: 1:7.

Answer: 4. 7: 1: 1:7.

Question 48. The process of transmission of characters from one generation to another is called :

1. Heredity
2. Mutation
3. Adaptation
4. Aenetics.

Answer: 1. Heredity

Question 49. Which of the following forms represents a pair of contrasting characters?

1. Allele
2. Phenotype
3. Homozygous
4. Heterozygous.

Answer: 4. Heterozygous.

Question 50. The appearance of Walnut-Comb in poultry on a cross between pure Pea-Comb and Rose-Comb animals is due to:

1. Duplicate genes
2. Complementary genes
3. Supplementary genes
4. Epistasis.

Answer: 3. Supplementary genes