Q.1
ion Q53) The allele which is unable to express its effect in the presence of another is called
  • a) Co - dominant
  • b) Supplementary
  • c) Complementary
  • d) Recessive
Q.2
ion Q54) Linkage is
  • a) directly related to crossing over
  • b) same as translocation
  • c) inversely related to crossing over
  • d) opposite to segregation
Q.3
ion Q55) Which disease results from the genetic inability to synthesize a single enzyme?
  • a) Diabetes
  • b) Phenylketonuria
  • c) Colour-blindness
  • d) Down's syndrome
Q.4
ion Q56) In the case of co-dominance, the F1 generation resembles:
  • a) Dominant parent
  • b) Recessive parent
  • c) Both the parents
  • d) None of the parents
Q.5
ion Q57) Which one from those given below is the period of Mendel's hybridisation experiments?
  • a) 1856 - 1863
  • b) 1840 - 1850
  • c) 1857 - 1869
  • d) 1870 - 1877
Q.6
ion Q58) A normal-visioned man whose father was colour-blind marries a woman whose father was also a colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind?
  • a) 100%
  • b) 0%
  • c) 25%
  • d) 50%
Q.7
ion Q59) A pure breeding pea plant with the dominant phenotype of character A and recessive phenotype of character B was crossed with another pure breeding plant with the recessive phenotype of character A and dominant phenotype character B. Offspring of this cross was crossed with a homozygous recessive for both the characters A and B. The following results were obtained. 22 were phenotypically dominant of A and recessive of B 4 were phenotypically recessive for both A and B 22 were phenotypically recessive for A and dominant for B. The results show that
  • a) genes A and B are linked
  • b) independent segregation of genes A and B
  • c) Mendelian dihybrid inheritance
  • d) polygenic inheritance.
Q.8
ion Q60) Grain colour in wheat is determined by three pairs of polygenes. Following the cross AABBCC (dark colour) X aabbcc (light colour), in F2 generation what proportion of the progeny is likely to resemble either parent?
  • a) None
  • b) Less than 5 percent
  • c) One third
  • d) Half
Q.9
ion Q61) Which of the following does not contribute to Mendel’s success?
  • a) Large sampling size
  • b) Statistical analysis
  • c) Performed experiments on single variety of pea
  • d) Performed experiments on successive generations
Q.10
ion Q62) Which among the following is not correct about incomplete/imperfect linkage?
  • a) According to the pattern of cross proposed by T.H. Morgan parental offspring are produced always more in number along with a few recombinants
  • b) The two genes linked on the same chromosomes are away from each other. So that they can be separated by crossing over.
  • c) Incomplete linkage is reported regarding all pairs of gene in Drosophila.
  • d) The dihybrid cross containing two characters eye colour and shape of wings show incomplete linkage.
Q.11
ion Q63) Recessive character is expressed in
  • a) F0
  • b) F1
  • c) F2
  • d) Never expressed.
Q.12
ion Q64) Consider the following statement and find out the incorrect one:
  • a) Advancement in Microscopy made the study of chromosomal behaviour possible.
  • b) The two alleles of a gene pair are located on homologous site on homologous chromosomes.
  • c) Experimental verification of chromosomal theory of Inheritance was done by T. H. Morgan et. Al.
  • d) Morgan Chose Drosophila as an experimental animal because it has variations that can be seen with high power of microscope.
Q.13
ion Q66) Mental retardation is associated with
  • a) Klinefelter’s syndrome
  • b) Haemophilia
  • c) Cystic fibrosis
  • d) Phenylketonuria
Q.14
ion Q67) In humans, curly hair is dominant (C) to straight hair (c). A woman who is heterozygote for curly hair marries to a normal man. What will be the probability of first and second child having curly hair?
  • a) ¼
  • b) ½
  • c) 1/8
  • d) 1/6
Q.15
ion Q68) Consider the following statements: (i) Every organisms has both autosomes and allosomes, the later determines sex. (ii) In man, males are heterogametic and females are homogametic. (iii) Females are heterogametic and males are homogametic in Drosophila. (iv) Males and females are heterogametic in birds. (v) Males are homogametic and females are heterogametic in hen. Of these statements:
  • a) (iii) and (v) are correct.
  • b) (i), (iii) and (iv) are wrong.
  • c) (iii) and (iv) are wrong.
  • d) (i) and (iv) are wrong.
Q.16
ion Q69) Due to non-disjunction of chromosomes during spermatogenesis, sperms carry both sex chromosomes (22A+XY) and some sperms do not carry any sex chromosome (22A+0). If these sperms fertilize normal eggs (22A+X), what types of genetic disorders appear among the offspring’s?
  • a) Turner's syndrome and Klinefelter's syndrome.
  • b) Down's syndrome and Klinefelter's syndrome.
  • c) Down's syndrome and Turner's syndrome.
  • d) Down's syndrome and cri-du-chat syndrome.
Q.17
ion Q70) Incomplete dominance was reported first in 4’o clock plant (Mirabilis jalapa) by:
  • a) Mendel.
  • b) Morgan.
  • c) Bateson.
  • d) Correns.
Q.18
ion Q71) Allele is the ... ...
  • a) Alternate trait of gene pair
  • b) Total number of genes for a trait
  • c) Total number of chromosomes
  • d) Total number of chromosomes of a haploid set.
Q.19
ion Q72) When there is no Possibility of independent assortment of genes during gametogenesis then What Will be the real ratio of F2 in dihybrd cross?
  • a) 9 : 3 : 3 : 1
  • b) 11 : 1 : 1 : 3
  • c) 12 : 1 : 1 : 2
  • d) 9 : 3 : 2 : 2
Q.20
ion Q73) The cross between heterozygous A blood group mother with B blood group father heterozygous).What will be the expected blood group of First filial generation.
  • a) AB group
  • b) A group
  • c) B group
  • d) O group
Q.21
ion Q74) Assertion (A) :- pedigree is same in colourblindness and haemophilia Reason (R) :- Colourblindness and haemophilia are X -linked recessive traits.
  • a) If both (A) and (R) are true and (R) is the correct explanation of (A)
  • b) If both (A) and (R) are true but (R) is not the correct explanation of (A)
  • c) If (A) is true but (R) is false
  • d) If both (A) and (R) are false.
Q.22
ion Q75) 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 is crossed with a plant that is rrtt.
  • a) 25% will be tall with red fruit
  • b) 50% will be tall with red fruit
  • c) 75% will be tall with red fruit
  • d) All the offspring will be tall with red fruit.
Q.23
ion Q76) Which one of the following conditions in human is correctly matched with its chromosomal abnormality / linkage ?
  • a) Erythro blastosis foetalis - X - linked
  • b) Down's syndrome - 44 autosomes +XXY
  • c) Kline Felter's syndrome - 44 autosomes +XXY
  • d) Colour blindness - Y - linked.
Q.24
ion Q77) A test cross is carried out to ......
  • a) determine the genotype of a plant at F1
  • b) Predict whether two traits are linked
  • c) assess the number of alleles of a gene
  • d) determine whether two species or varieties will breed successfully.
Q.25
ion Q78) A colour blind girl is rare because she will be born only when
  • a) Her mother and maternal grandfather were colour blind
  • b) Her father and maternal grandfather were colour blind
  • c) Her mother is colour blind and father has normal vision
  • d) Parents have normal vision but grandparents were colour blind.
Q.26
ion Q79) Lethal genes are those which
  • a) cause the death of the organism in which they are present
  • b) cause the death of the homozygous infant being formed
  • c) cause the death of heterozygous infant being formed
  • d) all of the above
Q.27
ion Q80) A person meets with an accident and great loss of blood has occurred. There is no time to analyse his blood group. It is safe to transfuse blood of
  • a) AB, RH+
  • b) AB, RH−
  • c) O, RH−
  • d) O, RH+
Q.28
ion Q81) 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
  • a) 1: 2: 1: Tall heterozygous: tall homozygous: Dwarf
  • b) 3: 1: Tall: Dwarf
  • c) 3: 1: Dwarf: Tall
  • d) 1: 2: 1: Tall homozygous: Tall heterozygous: Dwarf
Q.29
ion Q82) Which one of the following conditions correctly describes the manner of determining the sex in the given example?
  • a) XO type of sex chromosomes determine male sex in grasshopper
  • b) XO condition in humans as found in Turner syndrome, determines female sex
  • c) Homozygous sex chromosomes (XX) produce male in Drosophila
  • d) Homozygous sex chromosomes (ZZ) determine female sex in birds
Q.30
ion Q83) Phenotype of an organism is the result of:
  • a) mutations and linkages
  • b) Cytoplasmic effects and nutrition
  • c) environmental changes and sexual dimorphism
  • d) genotype and environmental interactions.
Q.31
ion Q84) If a homozygous red flowered plant is crossed with a homozygous white flowered plant, the offspring would be
  • a) half red-flowered
  • b) all red-flowered
  • c) half white-flowered
  • d) half pink- flowered.
Q.32
ion Q85) A child is born with an extra chromosome in each of its cells. This is usually the result of
  • a) non disjunction
  • b) crossing over
  • c) segregation
  • d) hybridization
Q.33
ion Q86) Which of the following conditions represents a case of co-dominance genes?
  • a) A gene expresses itself, suppressing the phenotypic effect of its alleles.
  • b) Genes that are similar in phenotypic effect when present separately, but when together interact to produce a different trait.
  • c) Alleles, both of which interact to produce a trait, which may or may not resemble either of the parental types.
  • d) Alleles, each of which produces an independent effect in a heterozygous condition.
Q.34
ion Q87) Which of the following statements are correct with respect to Law of dominance? i. Tall and dwarf traits were identical to their parental type and didn’t show any blending ii. Only one of the parental traits was expressed in F1 generation. iii. Both traits were expressed in the F2 generation. iv. The contrasting trait showed blending at F2 generation.
  • a) ii, iii and iv
  • b) i, ii and iii
  • c) ii and iii
  • d) i, ii, iii and iv
Q.35
ion Q88) Study the pedigree chart given below: What does it show?
unit-7_ch-2_que_no-88_img_no1.png
  • a) Inheritance of a condition like Phenylketonuria as an autosomal recessive trait
  • b) The pedigree chart is wrong as this is not possible
  • c) Inheritance of a recessive sex-linked disease like haemophilia
  • d) Inheritance of a sex-linked inborn error of metabolism like Phenylketonuria.
Q.36
ion Q89) Karyotype of the individual having Klinefelter’s syndrome shows:
  • a) An extra copy of 21st chromosome.
  • b) An extra copy of Y chromosome.
  • c) An extra copy of X chromosome.
  • d) Absence of Y chromosome.
Q.37
ion Q90) Gynaecomastia refers to
  • a) Masculine development in females
  • b) Development of breasts in males
  • c) Development of female characters in male
  • d) Reduced breasts in the female
Q.38
ion Q91) The behavior of chromosomes and genes can be compared with each other is best explained by which of the following statement?
  • a) occur in nucleus
  • b) both segregate at the time of gamete formation leading to transmittance of complete pair to a gamete.
  • c) Independent pairs (gene) or pair of chromosomes segregate independently of each other or of other pair.
  • d) The two alleles of a gene pair are located on homologous site on homologous chromosomes.
Q.39
ion Q92) You are studying the genetics of bean pigmentation in a particular variety of bean plant. A bean plant that produces grey beans is self-pollinated and the numbers of each progeny type produced are - 50 white beans 107 grey beans 38 black beans. Assuming that TWO genes govern the bean pigmentation trait, the genetic hypothesis that best explains the inheritance pattern of bean pigmentation would be:
  • a) dominant/recessive
  • b) incomplete dominance
  • c) Incomplete penetrance
  • d) recessive epistasis
Q.40
ion Q93) In the given pedigree chart select the correct statement:
unit-7_ch-2_que_no-93_img_no1.png
  • a) A & B are twins
  • b) A is younger than B
  • c) B is younger than A
  • d) Can’t determine the age of A & B
Q.41
ion Q94) The distance between gene A, B, C and D on a chromosome is as follows: A and C - 18 units A and B - 26 units A and D - 40 units B and C - 8 units B and D – 14 units The sequence of these genes would be-
  • a) ABCD
  • b) ACBD
  • c) ADCB
  • d) ACDB
Q.42
ion Q95) Select the correct statement from the ones given below with respect to dihybrid cross:
  • a) Tightly linked genes on the same chromosomes show higher recombination.
  • b) Tightly linked genes on the same chromosome show very few recombinations.
  • c) Genes far apart on the same chromosome show very few recombination.
  • d) Genes loosely linked on the same chromosome show similar recombination as the tightly linked genes.
Q.43
on Q176) In two pea plants having red (dominant) coloured flowers with unknown genotypes are crossed, 75% of the flowers are red and 25% are white. The genotypic constitution of the parents having red coloured flowers will be
  • a) both homozygous
  • b) one homozygous and other heterozygous
  • c) both heterozygous
  • d) both Hemizygous
Q.44
ion Q96) For a population of bacteria exposed to an antibiotic, most of them get killed but few survive and again increase their number. Choose the correct statement for the explanation of the experiment.
  • a) Some of the bacteria tried and successfully adapted to the new conditions in the Petri dish.
  • b) Some members of the bacteria population developed a resistance to the antibiotic immediately.
  • c) Some members of the bacteria population already had a resistance to the antibiotic so they were not killed.
  • d) Some of the bacteria quickly evolved into a new species that resists the antibiotic.
Q.45
ion Q97) Consider the following: (i) The family pedigree of queen Victoria shows a number of haemophilic descendents. (ii) The genetic makeup of the sperm determines the sex of the child in humans. (iii) The number of chromosomes is always equal in male and female. (iv) Gene segregates at the time of gamete formation such that only one of each pair is transmitted to the gamete.
  • a) Statements (i) and (ii) are wrong but (iii) and (iv) are correct.
  • b) Statements (i), (ii) and (iv) are correct but (iii) is wrong.
  • c) Statements (i), (ii) and (iii) are correct but (iv) is wrong.
  • d) All statements are correct.
Q.46
ion Q98) Pleiotropic gene:
  • a) Controls only one phenotype.
  • b) Controls several phenotypes.
  • c) Masks the expression of another non – allelic genes.
  • d) Inhibiting crossing over.
Q.47
ion Q99) Assertion: Chromosomal map is constructed on the basis of determination of distance between genes on the basis of percentage of recombinants. Reason: Percentage of recombinants is directly proportional to the distance between genes on the chromosome.
  • a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
  • b) Both Assertion and Reason are true but Reason is NOT the correct explanation of Assertion.
  • c) Assertion is true but Reason is false.
  • d) Both Assertion and Reason are false.
Q.48
on Q100) Cross XXYy × xxYy yields Xx YY:XxYy :Xxyy:xxyy offspring in the ratio of
  • a) 0 : 3 : 1 : 1
  • b) 1 : 2 : 1 : 0
  • c) 1 : 1 : 1 : 1
  • d) 1 : 2 : 1 : 1
Q.49
on Q101) The first person to induce mutations was
  • a) Hugo de Vries
  • b) T.H. Morgan
  • c) Sturtevant
  • d) H.J. Muller
Q.50
on Q102) Match each item in COLUMN I with one in COLUMN II and select your answer from the codes given:
SCIENTIST CONTRIBUTION
A. Francis Crick a. Breaking the genetic code
B. Nirenberg b. Established Caenorhabditis elegans as a model genetics study organism
C. Benzer c. Central dogma of molecular biology
D. Brenner d. Bacteriophage genetics
  • a) A =c B=a C= d D=b
  • b) A =c d B=a C= b D=d
  • c) A =a B=b C= c D=d
  • d) A =a B=c C= d D=b
0 h : 0 m : 1 s