Genetics MCQs Flashcards
1) Which of the following is the name of the small self-replicating DNA molecule found in bacteria that can be used as a cloning vector
a) Plasmid
b) Microsatellite
c) Chromatid
d) Amplicon
a
2) Which of the following is not correct in relation to DNA agarose gel electrophoresis
a) DNA migrates from the negative to the positive electrode
b) Smaller DNA molecules migrate slower than larger DNA molecules
c) Ultraviolet (UV) light is used to visualise the DNA bands in the gel
d) Ethidium bromide binds to the double stranded DNA
b
3) What enzyme is used to seal the DNA sugar phosphate backbone between the cloning vector DNA and the DNA insert during molecular cloning
a) DNA ligase
b) DNA sealing protein
c) Taq polymerase
d) DNA phosphatase
a
4) What is the theoretical number of polymer chain reaction (PCR) amplicons expected after forty cycles with a starting number of 1 target sequence
a) 40 X 2 X 1 = 80
b) 40 X 40^1 = 1600
c) 1 X 2^40 = 1,099,511,627,776
d) 40 X 1^2 = 40
c
5) During a typical polymerase chain reaction (PCR) cycle DNA samples are first heated to 94oC and then cooled to 55oC and then heated again to 72oC. What are each of the different temperature steps
a) 94oC = DNA denaturation step 55oC = enzyme extension step 72oC = primer annealing step
b) 94oC = Primer annealing step 55oC = DNA denaturation step 72oC = enzyme extension step
c) 94oC = DNA denaturation step 55oC = primer annealing step 72oC = enzyme extension step
d) 94oC = Enzyme extension step 55oC = DNA denaturation step 72oC = primer annealing step
c
6) Which of the following is not a component of a typical PCR reaction
a) Taq DNA polymerase enzyme
b) ddATP, ddCTP, ddGTP, and ddTTP dideoxynucleotides
c) dATP,dCTP, dGTP, and dTTP nucleotides
d) synthetic single stranded oligonucleotide DNA primers
b
7) The method of sequencing DNA using dideoxynuclotide triphosphates (ddNTPs) is called what
a) The Watson and Crick DNA sequencing method
b) The Sanger DNA sequencing method
c) The Pauling DNA sequencing method
d) The Mendel sequencing method
b
8) Which of the following is the correct name for the widely used gene that allows bacterial colonies carrying a DNA insert to be selected during the molecular cloning process based on their ability to metabolise the sugar X gal
a) LacZ
b) AmpR
c) Taq polymerase gene
d) DNA ligase gene
a
9) What is the target region of a genome that is amplified during the polymerase chain reaction (PCR)
a) Genomicon
b) Plasmid
c) Anticodon
d) Amplicon
d
10) EcoRI is a restriction enzyme that cuts DNA at a palindromic DNA sequence. Which of the following DNA sequences is palindromic and is the restriction sequence for EcoRI
a) 5’ – GAATTC – 3’
3’- CTTAAG – 5’
b) 5’ – GGGGGG-3’
3’- CCCCCC- 5’
c) 5’-TAATAA-3’
3’- ATTATT- 5’
d) 5’- CACACA-3’
3’- GTGTGT-5’
a
11) Which of the following nitrogenous bases is not found in biological DNA
a) Guanine
b) Adenine
c) Uracil
d) Cytosine
c
12) What is the function of the enzyme DNA polymerases
a) Catalyses the synthesis of a new DNA molecule using a template DNA strand
b) Catalyses the synthesis of a new polypeptide molecules using a template DNA strand
c) Catalyses the synthesis of a new RNA molecule using a template DNA strand
d) Catalyses the synthesis of a new polysaccharide molecule using a template DNA strand
a
14) What is the full term for the acronym Mrna
a) Messenger ribose acid
b) Messenger ribonucleic acid
c) Messenger ribosome acid
d) Messenger restriction acid
b
15) The biochemical process of translation is carried out by which molecule
a) DNA polymerase
b) RNA polymerase
c) The ribosome
d) DNA ligase
c
16) Which of the following will most dramatically change the amino acid sequence of a polypeptide
a) A single nucleotide substitution in the exon of a gene
b) Insertion of six nucleotides in the exon of a gene
c) A single nucleotide deletion in the exon of a gene
d) Deletion of three nucleotides in the exon of a gene
c
17) Examine the coding DNA sequence of a gene below (note only one of the strands is shown). A mutation has been discovered in this gene which changes a guanine nucleotide (G) to a adenine nucleotide (A) (Note the mutation is highlighted in underline and bold). The coding sequence of the normal gene and the mutated sequence of the gene are shown
Normal DNA sequence: TAC GGG CCC GTG
Normal mRNA sequence: AUG CCC GGG CAC
Normal polypeptide sequence: Met Pro Gly His
Mutant DNA sequence: TAC GG CCC GTA
Mutant mRNA sequence: AUG CCC GGG CAU
Mutant polypeptide sequence: Met Pro Gly His
a) A frameshift mutation
b) A missense mutation
c) A silent mutation
d) A nonsense mutation
c
18) When snapdragon plants that produce red flowers are crossed with snapdragon plants that produce white flowers the resulting offspring produce pink flowers. What Is the genetic term used to describe this phenomenon
a) Complete dominance
b) Imperfect dominance
c) Codominance
d) Incomplete dominance
d
19) Who is considered to be the father of genetics
a) Francis Crick
b) Gregor Mendel
c) James Watson
d) Charles Darwin
b
20) What is the meaning of the genetic term epistasis
a) The situation when one gene has a multiple phenotypic effects
b) The situation when one gene alters the expression of another gene
c) The situation when a trait is controlled by one gene
d) The situation when a trait is controlled by one or more gene
b
21) What is the correct description for a diploid organism with a pair of identical alleles for a character
a) Heterogeneous
b) Heterozygous
c) Homozygous
d) Homogeneous
c
22) Which of the following statements is true
a) Eukaryotic cells do not possess mitochondria in their cytoplasm
b) Prokaryotic cells do not contain proteins
c) Eukaryotic cells do not have a nuclear membrane
d) Prokaryotic cells do not have a nuclear membrane
d
23) How many rounds of cell division take place in eukaryotic meiotic cell division
a) Two
b) One
c) Four
d) Three
a
24) What is the missing phrase in the statement below? The chromatin in eukaryotic cell nuclei consists of ——-
a) Protein and carbohydrates
b) Carbohydrates and enzymes
c) Deoxyribonucleic acid and carbohydrates
d) Deoxyribonucleic acid and protein
d
25) If mottled overo stallions are matted with mottled overo mares what would the phenotypic proportions of foals born
a) 25% mottled overo foals 50% solid coloured foals 25% pure white still born foals
b) 50% mottled overo foals 25% solid coloured foals 25% pure white still born foals
c) 25% mottled overo foals 25% solid coloured foals 50% pure white still born foals
d) 33.3% mottled overo foals 33.3% solid coloured foals 33.3% pure white still born foals
b
26) A scientist crosses two true breeding varieties of pea plant. The first variety consists of plants that always produce yellow and round seeds. The second variety consists of plants that always produce green and wrinkled seeds. The F1 hybrid mating consists of plants that produce yellow and round seeds. What is the expected ratio of phenotypes in the F2 generation that is produced from mating the F1 plants with each other
a) 9 Green Wrinkled 3 Yellow Wrinkled 3 Green Round 1 Yellow Round
b) 9 Yellow Wrinkled 3 Yellow Round 3 Green Wrinkled 1 Green Round
c) 9 Green Round 3 Yellow Round 3 Green Wrinkled 1 Yellow Wrinkled
d) 9 Yellow Round 3 Yellow Wrinkled 3 Green Round 1 Green Wrinkled
d
28) What does r RNA stand for
a) Reproducible RNA
b) Replicated RNA
c) Regular RNA
d) Ribosomal RNA
d
29) Which of the following statements correctly describes complementary base pairing in DNA
A) Guanine base (G) is always base paired with cytosine C via two hydrogen bonds
B) Guanine base is always paired with adenine (A) base via two hydrogen bonds
C) A thymine base (T) is always base paired with adenine via two hydrogen bonds
D) A thymine base is always paired with cytosine base via three hydrogen bonds
c
30) What is the correct definition of the term cell cycle
a) The energy production system in a eukaryotic cell
b) The translation and transcription of encoded genetic information
c) The circular chromosome found in prokaryotic bacterial cells
d) The series of events in a eukaryotic cell from one cell division to the next
d
31) The ovine haploid chromosome number is 27. Ignoring recombination how many chromosomal combinations can result during meitotic cell division in sheep
a) 729
b) 54
c) 134,217,728
d) 443,426,488,243,038,000,000,000,000,000,000,000,000
c
32) What is the term used to describe the genotype of an X linked gene in male mammals
a) Homozygous
b) Heterozygous
c) Hemizygous
d) Homogeneous
c
33) What is the correct definition of the term pleiotrophy
a) The action of one gene modifying the effects of other genes
b) The movement of the spindle during eukaryotic cell division
c) The genetic effect of a single gene on multiple phenotypic traits
d) The genetic exchange that takes place between homologous chromosones during prophase I of meitotic cell division
c
34) Which of the following processes can enhance the evolutionary adaptation of a species to its environment
a) Mutation
b) Gene flow
c) Genetic drift
d) Natural or artificial selection
d
35) The frequency of cystic fibrosis (a recessive genetic disorder) in Ireland is approximately 1 in 1600. Therefore assuming Hardy-Weinberg Equilibrium which of the answers below represents the best estimate of the frequency of the mutant cystic fibrosis allele in the Irish population
a) 0.250
b) 0.025
c) 0.050
d) 0.500
b
36) Who first developed the concept of the genetic linkage map
a) James Watson and Francis Crick
b) Gregor Mendel
c) Thomas Hunt Morgan and Alfred Sturtevant
d) Linus Pauling
c
37) A colour blind woman has children with a man who has normal vision. What are the expected offspring proportions from this mating
a) 50% carrier females 50% colour blind males
b) 50% normal females 50% colour blind males
c) 50% colour blind females 50% normal males
d) 50% carrier females 50% normal males
a
38) S Wright, J.B.S Haldane and R.A fisher initiated which branch of genetics
a) Molecular genetics
b) Population genetics
c) Plant genetics
d) Animal genetics
b
39) In a region of west Africa with a high incidence of malaria, the frequency of sickle cell anaemia (a recessive genetic disorder) in the human population is 1 in 30. Therefore assuming Hardy Weinberg Equation (HWE) which of the answers below represents the best estimate of the mutant sickle cell anaemia in this population
a) 0.06
b) 0.18
c) 0.30
d) 0.03
b
40) Scientific evidence suggests that the cheetah (Acinoyx Jubatus) has undergone how many population constrictions that led to reductions in genetic variation
a) 2
b) 1
c) 3
d) None
a
41) An evolutionary founder event will act to
a) Decrease genetic drift
b) Increase rate of mutation
c) Increase genetic drift
d) Decrease the rate of mutation
c
42) Which of the following is the correct definition of the term genetic linkage
a) Two genes on different chromosomes that have a chemical bridge between them
b) The relationship between two genes that are physically close on the same chromosome and tend to be transmitted from parents to offspring as a single unit
c) Two genes that influence the same phenotypic trait
d) The condensation of chromatin to form discrete chromosomes prior to cell division
b
43) Which of the following nitrogenous bases is not found in biological DNA
a) Adenine
b) Cytosine
c) Guanine
d) Uracil
d
44) Which of the following are removed from transcribed protein coding RNA during mRNA processing in eukaryotes
a) Axons
b) Protons
c) Exons
d) Introns
d
45) Which of the following is not thought to cause mutation in the sequence or structure of DNA molecules
a) Exposure to chemical mutagen
b) Exposure to X Ray radiation
c) Exposure to a magnetic field
d) Exposure to Ultra Violet (UV) radiation
c
46) The biochemical process of transcription is carried out by which molecule
a) Restriction enzyme
b) RNA polymerase
c) The ribosome
d) DNA ligase
b
47) The ribosome is composed of
a) Protein and DNA
b) Protein and RNA
c) Carbohydrate and RNA
d) Protein and Carbohydrate
b
48) Which of the following discovered the three dimensional structure of DNA
a) Gregor Mendel
b) James Watson and Francis Crick
c) Oswald Avery
d) Charles Darwin
b
49) Which of the following terms does not relate to the structure of DNA
a) Hydrogen bond
b) Purine
c) Pyrimidine
d) Peptide
d
50) What is the function of the retroviral enzyme reverse transcriptase
a) Enables virus to enter cellular membranes of host cell
b) Translates host DNA into viral proteins
c) Transcribes a DNA molecule from a single stranded viral RNA template
d) Lyses cell membrane to allow viral particles infect other cells
c
51) Which of the following is not correct in relation to DNA agarose gel electrophoresis
a) Ethidium Bromide binds to double stranded DNA
b) DNA migrates from the positive electrode to the negative electrode
c) Smaller DNA molecules migrate faster than larger DNA molecules
d) UV light is used to visualise the DNA bands in the gel
b
52) The restriction enzyme BamHI cuts DNA molecules at the following restriction site
5’ – GGATCC -3’
3’ – CCTAGG-5’
How many double stranded fragments will results if the following DNA molecule is cut with BamHI
5’ TTAACGATGCGAAGGATCC AACGTTTAGGCCGAATTCTGGATCCGAATTCTTACATCCA 3’
3’ AATTGCTACGCTT CCTAGGTTGCAAATCCGGCTTAAGGACCTAGG CTTAAGAATGTAGGT
a) 2
b) 5
c) 3
d) 4
b
53) What is the Sanger laboratory method used for
a) Determining the sequence of bases in a DNA molecule
b) Cutting a DNA molecule into smaller fragments
c) Transcribing An RNA molecule from a DNA template molecule
d) Translating and RNA molecule into a polypeptide chain
a
54) What is the theoretical number of polymerase chain reaction (PCR) amplicons expected after 40 cycles with a starting number of 10 sequences
a) 40 X 210 = 40, 960
b) 40 X 102= 4,000
c) 2 X 1040= 20,000,000,000,000,000,000,000,000,000,000,000,000
d) 10 X 240= 10, 995, 116, 277, 760
d
55) Which of the following is the correct name for a widely used gene that confers resistance to an antibiotic during bacterial cloning of recombinant DNA
a) ampR
b) andR
c) anpR
d) amaR
a