1. Question 1 of 100

   The Bt toxin used in Bt crops comes from

   A a fungus B a virus C the bacterium Bacillus thuringiensis D a plant
2. Question 2 of 100

   After 10 cycles of PCR starting from a single DNA molecule, the theoretical number of copies is

   A 1,024 B 100 C 512 D 20
3. Question 3 of 100

   The lac operon of E. coli was described by

   A Jacob and Monod B Watson and Crick C Meselson and Stahl D Hershey and Chase
4. Question 4 of 100

   The number of hydrogen bonds between A–T and G–C base pairs is respectively

   A 3 and 2 B 2 and 2 C 2 and 3 D 3 and 3
5. Question 5 of 100

   The first genetically engineered human medicine, approved in 1982, was

   A penicillin B interferon C aspirin D human insulin (Humulin)
6. Question 6 of 100

   According to Chargaff's rule in DNA,

   A the amount of A equals T and G equals C B A equals G C A equals C D T equals G
7. Question 7 of 100

   Mendel's law of segregation states that

   A all traits are inherited together B genes mutate often C alleles blend permanently D the two alleles of a gene separate during gamete formation
8. Question 8 of 100

   The Cartagena Protocol on Biosafety regulates

   A the transboundary movement of living modified organisms B ozone-depleting substances C trade in wild animals D plastic waste
9. Question 9 of 100

   DNA ligase is used in genetic engineering to

   A cut DNA B copy RNA C join DNA fragments D break down proteins
10. Question 10 of 100

    Reverse transcriptase is an enzyme that

    A synthesises RNA from DNA B cuts DNA C synthesises DNA from an RNA template D joins DNA fragments
11. Question 11 of 100

    Genetic counselling helps

    A to cure all diseases B to make clones C to change blood groups D families understand the risk of inherited disorders
12. Question 12 of 100

    Turner syndrome is characterised by the chromosomal pattern

    A 47, XXY B 45, X C 47, XXX D 46, XY
13. Question 13 of 100

    A test cross is a cross of an individual of unknown genotype with a

    A homozygous recessive individual B homozygous dominant individual C heterozygous individual D different species
14. Question 14 of 100

    Bt cotton is a

    A genetically modified crop B hybrid animal C fertiliser D pesticide spray
15. Question 15 of 100

    A trait that appears in a heterozygous individual is called

    A dominant B recessive C mutant D lethal
16. Question 16 of 100

    A transgenic organism is one that

    A has lost a gene B has extra chromosomes only C contains a gene from another species D is a hybrid by crossing
17. Question 17 of 100

    Epistasis is the

    A dominance of one allele over its partner B gain of a chromosome C deletion of a gene D interaction in which one gene masks or modifies the expression of another gene
18. Question 18 of 100

    Human insulin is produced on a large scale using genetically engineered

    A bacteria (E. coli) B viruses only C mushrooms D algae only
19. Question 19 of 100

    A sudden, permanent change in the DNA sequence is called a

    A replication B transcription C translation D mutation
20. Question 20 of 100

    Colour blindness is more common in males because it is

    A a Y-linked dominant trait B autosomal dominant C an X-linked recessive trait D a mitochondrial trait
21. Question 21 of 100

    The double helix model of DNA was proposed by

    A Mendel and Morgan B Hooke and Schleiden C Pasteur and Koch D Watson and Crick
22. Question 22 of 100

    The gene gun (biolistic) method delivers DNA into cells using

    A viruses only B sound waves C DNA-coated microscopic metal particles D liposomes only
23. Question 23 of 100

    In a population in Hardy–Weinberg equilibrium, 4% have a recessive trait (q² = 0.04). The percentage of carriers is

    A 4% B 16% C 32% D 64%
24. Question 24 of 100

    Mendel performed his famous experiments on

    A fruit flies B garden pea plants C mice D bacteria
25. Question 25 of 100

    The sex of a human child is determined by the

    A mother's chromosome B father's chromosome (X or Y sperm) C blood group D diet of the mother
26. Question 26 of 100

    DNA fingerprinting, developed by Alec Jeffreys, mainly analyses

    A short tandem repeats (STRs) that vary between individuals B chromosome number C the sex of the person only D blood groups
27. Question 27 of 100

    The AB blood group is an example of

    A codominance B incomplete dominance C recessiveness D mutation
28. Question 28 of 100

    In a cross Tt × Tt, the percentage of offspring with the recessive phenotype is

    A 50% B 75% C 25% D 0%
29. Question 29 of 100

    Recombinant DNA technology involves

    A cloning an entire animal B making a protein from sugar C filtering water D combining DNA from different sources
30. Question 30 of 100

    Chromosomes are made of

    A lipids and sugars B RNA only C cellulose D DNA and proteins
31. Question 31 of 100

    In Mendel's monohybrid cross, the phenotypic ratio in the F₂ generation is

    A 1 : 1 B 9 : 3 : 3 : 1 C 1 : 2 : 1 D 3 : 1
32. Question 32 of 100

    In the CRISPR-Cas9 system, the Cas9 enzyme is directed to the target DNA by

    A a restriction site only B a ribosome C a guide RNA D a plasmid vector only
33. Question 33 of 100

    Sanger DNA sequencing makes use of

    A restriction enzymes only B antibodies C ribosomes D dideoxynucleotides that terminate chain elongation
34. Question 34 of 100

    Sickle cell anaemia is caused by

    A a missing chromosome B a point mutation in the haemoglobin gene C a viral infection D vitamin deficiency
35. Question 35 of 100

    The observable physical characteristics of an organism are its

    A genotype B phenotype C karyotype D genome
36. Question 36 of 100

    In eukaryotic mRNA processing, introns are

    A added B translated into protein C removed by splicing D converted into DNA
37. Question 37 of 100

    A silent mutation does not change the amino acid because of the

    A degeneracy of the genetic code B presence of introns C action of ligase D presence of telomeres
38. Question 38 of 100

    Vaccines work by

    A stimulating the immune system to produce memory against a germ B killing all germs directly C supplying antibiotics D replacing blood
39. Question 39 of 100

    A karyotype is

    A a blood test B a type of protein C a display of the chromosomes of a cell arranged in pairs D a vaccine
40. Question 40 of 100

    The four nitrogenous bases in DNA are

    A A, U, G and C B A, T, G and C C A, T, U and C D A, B, C and D
41. Question 41 of 100

    The correct order of steps in a PCR cycle is

    A annealing → denaturation → extension B denaturation → annealing → extension C extension → annealing → denaturation D denaturation → extension → annealing
42. Question 42 of 100

    A nucleotide of DNA consists of

    A an amino acid and a sugar B a sugar, a phosphate group and a nitrogenous base C a fatty acid and a phosphate D only bases
43. Question 43 of 100

    Mendel's law of independent assortment states that

    A all genes are linked B traits blend C dominant alleles always win D genes for different traits are inherited independently of each other
44. Question 44 of 100

    Selective breeding is the

    A random mating of any organisms B choosing of parents with desirable traits to produce better offspring C making clones in laboratory D use of radiation only
45. Question 45 of 100

    Monoclonal antibodies are produced using

    A PCR only B hybridoma technology C electrophoresis only D plant tissue culture
46. Question 46 of 100

    The central dogma of molecular biology is

    A protein → RNA → DNA B DNA → RNA → protein C RNA → protein → DNA D DNA → protein → RNA
47. Question 47 of 100

    In a cross AaBb × AaBb, the probability of an offspring with genotype aabb is

    A 1/4 B 1/16 C 1/8 D 3/16
48. Question 48 of 100

    The number of pairs of chromosomes in a human cell is

    A 46 B 22 C 23 D 48
49. Question 49 of 100

    The Philadelphia chromosome, found in chronic myeloid leukaemia, results from a

    A deletion of chromosome 5 B translocation between chromosomes 9 and 22 C trisomy of chromosome 21 D loss of the Y chromosome
50. Question 50 of 100

    RNA interference (RNAi) silences genes using

    A small interfering RNA (siRNA) B large DNA fragments C lipid droplets D plasmid DNA only
51. Question 51 of 100

    A nonsense mutation

    A changes no codon B adds three nucleotides C swaps the chromosomes D converts an amino-acid codon into a stop codon
52. Question 52 of 100

    Yeast is used in

    A making plastic B making glass C making steel D bread making and brewing
53. Question 53 of 100

    A gene is a

    A whole chromosome B type of cell C type of protein only D segment of DNA that codes for a trait or protein
54. Question 54 of 100

    Biotechnology is the use of

    A only machines to make products B only chemicals to make products C only solar energy D living organisms or their products to make useful products
55. Question 55 of 100

    Phenylketonuria (PKU) is an inherited disorder of

    A bone growth B blood clotting C eyesight only D amino acid (phenylalanine) metabolism
56. Question 56 of 100

    Dolly the sheep was produced by

    A fertilisation in a test tube B cell fusion with bacteria C gene gun method D somatic cell nuclear transfer
57. Question 57 of 100

    Induced pluripotent stem cells (iPSCs) were developed by reprogramming adult cells with

    A restriction enzymes B Yamanaka factors C antibiotics D Taq polymerase
58. Question 58 of 100

    The human ABO blood group system has

    A two blood groups B three blood groups only C eight blood groups D four blood groups: A, B, AB and O
59. Question 59 of 100

    A plasmid used to carry a foreign gene into a host cell is called a

    A primer B probe C antigen D vector
60. Question 60 of 100

    Alternative forms of the same gene are called

    A alleles B chromosomes C genomes D plasmids
61. Question 61 of 100

    The Ti plasmid of Agrobacterium tumefaciens is used to

    A transfer genes into plant cells B clone animals C sequence DNA D produce antibiotics
62. Question 62 of 100

    Epigenetic changes such as DNA methylation

    A change the base sequence B delete genes C alter gene expression without changing the DNA sequence D convert DNA to RNA
63. Question 63 of 100

    mRNA vaccines against COVID-19 work by delivering

    A live whole virus B antibiotic molecules C mRNA that instructs cells to make the viral spike protein D viral DNA only
64. Question 64 of 100

    The test cross of a dihybrid (AaBb × aabb) gives the phenotypic ratio

    A 9 : 3 : 3 : 1 B 1 : 1 : 1 : 1 C 3 : 1 D 1 : 2 : 1
65. Question 65 of 100

    Gene therapy aims to

    A grow bigger plants B produce antibiotics C treat genetic disorders by replacing or repairing faulty genes D clone animals
66. Question 66 of 100

    A frameshift mutation is caused by

    A substitution of one base by a similar one B duplication of whole chromosomes C a change in sugar D insertion or deletion of nucleotides not in multiples of three
67. Question 67 of 100

    Recombination frequency between two linked genes is expressed in

    A map units (centimorgans) B decibels C sieverts D daltons
68. Question 68 of 100

    A mature eukaryotic mRNA has a

    A 3′ cap and poly-U tail B no tail or cap C 5′ cap and a poly-A tail D double strand
69. Question 69 of 100

    PCR (polymerase chain reaction) is used to

    A separate proteins B make many copies of a specific DNA segment C cut proteins D cut DNA only
70. Question 70 of 100

    The enzyme that unwinds the DNA double helix at the replication fork is

    A helicase B ligase C RNA polymerase D amylase
71. Question 71 of 100

    The Hershey–Chase experiment used radioactive ³²P and ³⁵S to show that the genetic material of bacteriophage is

    A protein B lipid C carbohydrate D DNA
72. Question 72 of 100

    Heredity is the

    A transmission of characters from parents to offspring B change of species C growth of organisms D division of cells
73. Question 73 of 100

    The Human Genome Project was aimed at

    A cloning humans B mapping and sequencing all human genes C making new vaccines D studying only brain cells
74. Question 74 of 100

    DNA polymerase can add new nucleotides only to the

    A 3′ end of a growing strand (synthesis in the 5′→3′ direction) B 5′ end of a growing strand C middle of a strand D phosphate groups only
75. Question 75 of 100

    Albinism is caused by the absence of

    A melanin pigment B haemoglobin C chlorophyll D insulin
76. Question 76 of 100

    The father of genetics is

    A Charles Darwin B Louis Pasteur C Robert Hooke D Gregor Mendel
77. Question 77 of 100

    Dolly, the first cloned mammal, was a

    A goat B cow C sheep D monkey
78. Question 78 of 100

    Gel electrophoresis separates DNA fragments according to their

    A colour B size C taste D temperature only
79. Question 79 of 100

    Messenger RNA (mRNA) carries

    A amino acids B the genetic message from DNA to ribosomes C ribosome structure D lipids
80. Question 80 of 100

    Two carrier parents for an autosomal recessive disorder have two children. The probability that both are affected is

    A 1/4 B 1/16 C 1/8 D 1/2
81. Question 81 of 100

    DNA fingerprinting is used in

    A measuring blood pressure B making vaccines only C forensic investigation and paternity testing D testing eyesight
82. Question 82 of 100

    The phenotypic ratio in the F₂ generation of a dihybrid cross is

    A 3 : 1 B 9 : 3 : 3 : 1 C 1 : 1 : 1 : 1 D 1 : 2 : 1
83. Question 83 of 100

    A person who carries a recessive allele for a disease but shows no symptoms is called a

    A carrier B mutant C clone D hybrid
84. Question 84 of 100

    Southern blotting is used to detect

    A specific DNA sequences B specific RNA sequences C specific proteins D specific lipids
85. Question 85 of 100

    Golden rice is genetically modified to contain

    A insulin B vitamin C C beta-carotene (provitamin A) D iron only
86. Question 86 of 100

    In humans, females have the sex chromosomes

    A XY B XO C XX D YY
87. Question 87 of 100

    If the template strand of DNA is 3′-TACGGA-5′, the mRNA transcribed from it is

    A 5′-UACGGA-3′ B 5′-ATGCCT-3′ C 5′-TACGGA-3′ D 5′-AUGCCU-3′
88. Question 88 of 100

    When a red-flowered snapdragon is crossed with a white-flowered one, the F₁ are pink. This is an example of

    A codominance B incomplete dominance C multiple alleles D epistasis
89. Question 89 of 100

    Identical twins develop from

    A two eggs fertilised by two sperms B an unfertilised egg C a single fertilised egg that splits D two sperms and no egg
90. Question 90 of 100

    Klinefelter syndrome is characterised by the chromosomal pattern

    A 47, XXY B 45, X C 46, XX D 47, XYY
91. Question 91 of 100

    Haemophilia is a disorder in which

    A blood fails to clot properly B red cells are too numerous C bones are brittle D insulin is not produced
92. Question 92 of 100

    Which of the following is a mutagen?

    A Visible light B Water C X-rays D Oxygen
93. Question 93 of 100

    The genotype of a person with blood group O is

    A IᴬIᴮ B Iᴬi C IᴮIᴮ D ii
94. Question 94 of 100

    Restriction enzymes are called molecular scissors because they

    A join DNA fragments B cut DNA at specific sequences C copy DNA D digest proteins
95. Question 95 of 100

    Down syndrome is caused by an extra copy of chromosome

    A 18 B 13 C X D 21
96. Question 96 of 100

    Tissue culture is used to

    A kill bacteria B extract oxygen C grow plants or cells from small pieces under sterile conditions D make glass
97. Question 97 of 100

    Meselson and Stahl's experiment, using heavy nitrogen (¹⁵N), proved that DNA replication is

    A conservative B semi-conservative C dispersive D random
98. Question 98 of 100

    The conversion of milk into curd is done by

    A Lactobacillus bacteria B Penicillium C yeast D Amoeba
99. Question 99 of 100

    Taq polymerase, used in PCR, is obtained from

    A E. coli B Penicillium C Thermus aquaticus, a heat-resistant bacterium D Bacillus thuringiensis
100. Question 100 of 100

     Penicillin, the first antibiotic, is obtained from

     A a virus B the fungus Penicillium C a plant root D a bacterium only

You can practise as a guest, but sign in to save your score and track your progress.