Free NEET Biology multiple-choice questions on Mendelian Inheritance. Attempt each question and reveal the answer with a full explanation.
In order to find out the different types of gametes produced by a pea plants having the genotype AaBb, it should be crossed to a plant with the genotype - AaBb aabb AABB aaBB Which Mendelian idea is depicted by a cross in which the F 1 generation resembles both the parents ? (1) Incomplete dominance (2) Law of dominance (3) Inheritance of one gene (4) Co-dominance If both parents are carriers for thalassemia, which is an autosomal recessive disorder, what are the chances of pregnancy resulting in an affected child? (1) No chance (2) 50% (3) 25% (4) 100% 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 : 2 : 1 :: Tall homozygous : Tall heterozygous : Dwarf 1 : 2 : 1 :: Tall heterozygous : Tall homozygous : Dwarf 3 : 1 :: Tall : Dwarf 3 : 1 :: Dwarf : Tall Which one of the following is not true for the experiments of Mendel on pea ? His experiments had large sampling size He chose characters of two contrasting states He used true-breeding lines His observations were based on natural, open pollination Identify the wrong statement with reference to the gene 'I' that controls ABO blood groups. A person will have only two of the three alleles. When I A and I B are present together, they express same type of sugar. Allele 'i' does not produce any sugar. The gene (I) has three alleles. How many true breeding pea plant varieties did Mendel select as pairs, which were similar except in one character with contrasting traits? 2 14 8 4 The production of gametes by the parents, formation of zygotes, the F 1 and F 2 plants, can be understood from a diagram called : Punch square Punnett square Net square Bullet square In a cross between a male and female, both heterozygous for sickle cell anaemia gene, what percentage of the progeny will be diseased? 75% 25% 100% 50% Given below are two statements : Statement I : Mendel studied seven pairs of contrasting traits in pea plants and proposed the Laws of Inheritance. Statement II : Seven characters examined by Mendel in his experiment on pea plants were seed shape and colour, flower colour, pod shape and colour, flower position and stem height. In the light of the above statements, choose the correct answer from the options given below : 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 Both Statement I and Statement II are correct Which of the following occurs due to the presence of autosome linked dominant trait? Myotonic dystrophy Haemophilia Thalassemia Sickle cell anaemia Phenotype of an organism is the result of- Mutations and linkages Cytoplasmic effects and nutrition Environmental changes and sexual dimorphism Genotype and environment interactions The phenomenon of pleiotropism refers to Presence of several alleles of a single gene controlling a single crossover Presence of two alleles, each of the two genes controlling a single trait A single gene affecting multiple phenotypic expression More than two genes affecting a single character Which one of the following symbols represents mating between relatives in human pedigree analysis? Match List I with List II array ll List I & List II A. Two or more alternative forms of a gene & I. Back cross B. Cross of F 1 progeny with homozygous recessive parent & II. Ploidy C. Cross of F 1 progeny with any of the parents & III. Allele D. Number of chromosome sets in plant & IV. Test cross array Choose the correct answer from the options given below: A-I, B-II, C-III, D-IV A-II, B-I, C-III, D-IV A-III, B-IV, C-I, D-II A-IV, B-III, C-II, D-I 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 you cross it? BB bb Bb BB/Bb Genes R and Y follow independent assortment. If RRYY produce round yellow seeds and rryy produce wrinkled green seeds, what will be the phenotypic ratio of the F2 generation? Phenotypic ratio - 9 : 7 Phenotypic ratio - 1 : 2 : 1 Phenotypic ratio - 3 : 1 Phenotypic ratio - 9 : 3 : 3 : 1 What is the pattern of inheritance for polygenic trait? X-linked recessive inheritance pattern Mendelian inheritance pattern Non-mendelian inheritance pattern Autosomal dominant pattern If a trait is controlled by three pairs of polygenes ( n=3 ), how many different phenotypes are possible in the F 2 generation? 7 6 9 27 In a population, if the frequency of the dominant phenotype is 0.19, what is the frequency of the recessive allele ' q ', assuming Hardy-Weinberg equilibrium? 0.9 0.81 0.1 0.01 In the human population, the ABO blood group is controlled by three alleles: I A , I B , and i . How many different genotypes are possible in the population for this character? 6 4 3 9 Which Mendelian law states that although the parents contain two alleles, during gamete formation, the factors or alleles of a pair separate from each other such that a gamete receives only one of the two factors? Law of Segregation Law of Dominance Law of Independent Assortment Law of Unit Characters How many different kinds of gametes will be produced by a plant having the genotype AABbCC ? Three Four Nine Two A test cross is used to determine the genotype of a dominant phenotype plant. It involves crossing the unknown plant with a: Homozygous recessive parent Homozygous dominant parent Heterozygous parent F1 hybrid A common test to find the genotype of a hybrid is by crossing of one F 2 progeny with female parent studying the sexual behaviour of F 1 progenies crossing of one F 1 progeny with male parent crossing of one F 2 progeny with male parent. Study the pedigree chart given below : What does it show ? Inheritance of a recessive sex-linked disease like haemophilia Inheritance of a sex-linked inborn error of metabolism like phenylketonuria Inheritance of a condition like phenylketonuria as an autosomal recessive trait The pedigree chart is wrong as this is not possible Select the incorrect statement from the following : Baldness is a sex limited trait Linkage is an exception to the principle of independent assortment in heredity. Galactosemia is an inborn error of metabolism Small population size results in random genetic drift in a population If two persons with 'AB' blood group marry and have sufficiently large number of children, these children could be classified as 'A' blood group : 'AB' blood group : 'B' blood group in 1 : 2 : 1 ratio. Modern technique of protein electrophoresis reveals presence of both 'A' and 'B' type proteins in 'AB' blood group individuals. This is an example of Codominance Incomplete dominance Partial dominance Complete dominance Fruit colour in squash in an example of :- Recessive epistasis Dominant epistasis Complementary genes Inhibitory genes Match the terms in Column-I with their description in Column-II and array ll Column-I & Column-II (a) Dominance & (i) Many genes govern a single character (b) Codominance & (ii) In a heterozygous organism only one allele expresses itself (c) Pleiotropy & (iii) In a heterozygous organism both alleles express themselves fully (d) Polygenic inheritance & (iv) A single gene influences many characters array choose the correct option : a-ii, b-i, c-iv, d-iii a-ii, b-iii, c-iv, d-i a-iv, b-i, c-ii, d-iii a-iv, b-iii, c-i, d-ii Pick out the correct statements : (a) Haemophilia is a sex-linked recessive disease (b) Down's syndrome is due to aneuploidy (c) Phenylketonuria is an autosomal recessive gene disorder. (d) Sickle cell anaemia is a X-linked recessive gene disorder (a) and (d) are correct (b) and (d) are correct (a), (c) and (d) are correct (a), (b) and (c) are correct Which of the following pairs is wrongly matched? XO type sex determination : Grasshopper ABO blood grouping : Co-dominance Starch synthesis in pea : Multiple alleles T.H. Morgan : Linkage Select the correct statement Spliceosomes take part in translation Punnett square was developed by a British scientist Franklin Stahl coined the term “linkage” Transduction was discovered by S. Altman Which one of the following is an example of polygenic inheritance ? Flower colour in Mirabilis jalapa Production of male honey bee Pod shape in garden pea Skin colour in humans Which of the following characteristics represent ‘Inheritance of blood groups’ in humans? a. Dominance b. Co-dominance c. Multiple allele d. Incomplete dominance e. Polygenic inheritance b, d and e a, b and c b, c and e a, c and e In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F 1 generation pink flowers were obtained. When pink flowers were selfed, the F 2 generation showed white, red and pink flowers. Choose the incorrect statement from the following : (1) Law of Segregation does not apply in this experiment (2) This experiment does not follow the Principle of Dominance. (3) Pink colour in F 1 is due to incomplete dominance. (4) Ratio of F 2 is 1 4 (Red) : 2 4 (Pink) : 1 4 (White) Select the correct match Phenylketonuria – Autosomal dominant trait Sickle cell anaemia – Autosomal recessive trait, chromosome-11 Thalassemia – X linked Haemophilia – Y linked 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 F 2 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: A, B and C only A, C, D and E only B, C and D only A, B, C, D and E A pink flowered Snapdragon plant was crossed with a red flowered Snapdragon plant. What type of phenotype/s is/are expected in the progeny? Only red flowered plants Red flowered as well as pink flowered plants Only pink flowered plants Red, Pink as well as white flowered plants 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. I B i/I A i/ii B. I B I B /I A I A /ii C. I A I B /ii/I B i D. I A i/I B i/I A i E. iI B /iI A /I A I B Choose the most appropriate answer from the options given below : (1) A only (2) B only (3) C & B only (4) D & E only Match List I with List II : array llll ; & List-I & ; & List-II A. & Incomplete dominance & I. & Human skin colour B. & Co-dominance & II. & Inheritance of flower colour in Antirrhinum sp. C. & Pleiotropy & III. & Phenylketonuria disease in humans D. & Polygenic inheritance & IV. & ABO blood groups array A-I, B-IV, C-III, D-II A-I, B-III, C-II, D-IV A-II, B-IV, C-III, D-I A-II, B-I, C-III, D-IV What is the probability of having children with ‘O’ blood group, where both mother and father are heterozygous for ‘A’ and ‘B’ blood group, respectively? 0% 50% 25% 75% In a cross between two sweet pea plants with white flowers ( CCpp and ccPP ), the F 1 generation produces purple flowers. If the F 1 generation is self-pollinated, what is the expected phenotypic ratio in F 2 ? 9 Purple : 7 White 9 Purple : 3 White : 4 Pink 12 Purple : 3 White : 1 Pink 15 Purple : 1 White In the sweet pea plant ( Lathyrus odoratus ), the presence of two dominant genes C and P together is required for purple flower color. A cross between CcPp and CcPp results in a phenotypic ratio of: 9:7 9:3:4 12:3:1 15:1 Test cross involves- Crossing between two genotypes with recessive trait Crossing between two F₁ hybrids Crossing the F₁ hybrid with a double recessive genotype Crossing between two genotypes with dominant trait In Mendel's experiments with garden pea, round seed shape (RR) was dominant over wrinkled seeds (rr), yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the expected phenotypes in the F₂ generation of the cross RRYY × rryy ? Only round seeds with green cotyledons Only wrinkled seeds with yellow cotyledons Only wrinkled seeds with green cotyledons Round seeds with yellow cotyledons, and wrinkled seeds with yellow cotyledons For a person with blood group 'O', which of the following is not a possible combination of parents' blood group genotypes? Father : I A i and Mother : I B i Father : I A i and Mother : I A i Father : I B i and Mother : I B i Father : I A I B and Mother : I A i Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : In an experiment, Mendel observed that the F1 progeny plants are all tall and none are dwarf. Reason R : Stem height is a contrasting trait, with tall being dominant and dwarf being recessive. In the light of the above statements, choose the most appropriate 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 Inheritances of skin colour in humans is an example of point mutation polygenic inheritance codominance chromosomal aberration. 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 you expect in F 1 generation ? 9 : 1 1 : 3 3 : 1 50 : 50 A human male produces sperms with the genotypes AB, Ab, aB, and ab pertaining to two diallelic characters in equal proportions. What is the corresponding genotype of this person? AaBB AABb AABB AaBb. The most popularly known blood grouping is the ABO grouping. It is named ABO and not ABC, because "O" in it refers to having : No antigens A and B on RBCs Other antigens besides A and B on RBCs Overdominance of this type on the genes for A and B types One antibody only-either anti-A and anti-B on the RBCs