1. In Humans, many types of cancers have been linked to?
A. Duplications
B. Inversions
C. translocations
D. deletions
E all of these
2. 5- bromoouracil is mutagenic because it is a(n)
a. base-modifying agent
b. base analog
c. intercalating agent
d. alkylating agent.
3.Ultraviolet radiation creates __________ in DNA
A. 5-methyl cytosine residues
B. breakages
C point mutations
D. mutational hot spots
E thymine dimers
4. The telomeres of chromosomes is composed of
A. heterochromatin
b. nucleosome
c. histone
d. achromatic
5. In eukaryotes, a replicon is
a. the distance between the origin of replication and thetermination of replication
b. a single chromosome
c. the entire genome
d. one DNA strand of a single chromosome
6. In a nonreciprocal interchomosomal translocation, a segment of achromosome is
a. exchanged with an identical segment on a differentchromosome
b. exchanged with an identical segment on a sister chromatid
c. transferred to a different chromosome without a reciprocalexchange of genetic material
d. transferred to a new location on the same chromosome without areciprocal exchange of genetic material
7. Somatic mutations are always.
a. spontaneous
b. carcinogenic
c. heritable
d. lethal
e. none of these
8. A woman with an XO genotype is
a. aneuploid
b. euploid
c. diploid
d. poluploid
9. Spontaneous mutations may occur as a result of
a. all of these
b. errors in DNA replication
c. transposition
d. none of these
e. normal cell biochemistry
10. In the semi conservative model of DNA replication, progenydouble helices consist of
a. one parental DNA strand and one new strand
b. one parental DNA strand and one new RNA strand
c. two new RNA strands
d. two parental DNA strands
e. two new DNA strands
11. A mutation in a gene may alter a cellâs
a. phenotype
b. genotype and phenotype
c. genotype
12. During replication, the direction of synthesis of new DNA fromthe leading strand is
a. both 5â to 3â and 3â to 5â
b. none of these
c. 3â to 5â
d. from left to right only
e. 5â to 3â only
13. A mutation that results in a switch from a purine-pyramidingbase pair to a pyramiding-purine base pair is a _________mutation.
a. neutral
b. transition
c. missense
d. transversion
e. nonsense
14. A trisomic human cell would contain how many chromosomes?
a. 45
b. 46,
c. 47.
d. 48
15. In a strand of DNA, a _____________ bond connects the phosphategroup of one nucleotide to the sugar of the adjacentnucleotide
a. hydrogen
b. ester
c. phosphodiester
d. phosphate
e. disulfide
16. Cri-du-chat syndrome is caused by which type of chromosomalmutation?
a. deletion
b. duplication
c. translocation
d. transversion
e. inversion
17. During replication, the role of DNA primase is to
a. add nucleotide to the growing DNA chain
b. synthesize a short chain for RNA
c. untwist the double helix at the origin of replication
d. relax the super coiling of the double helix
e. synthesize the primo some
18. A(n) ____________ inversion involves the Centro mere
a. chromocentric
b. paracentric
c. epicentric
d. percentric
e. concentric
19. Which of the following substances mutates DNA by intercalatingbetween adjacent base pairs?
a. methyl methane sulfonate
b. all of these
c. nitrous acid
d. 2-amino urine
e. acridine orange
20. A molecule of RNA is always
a. double stranded
b. helical
c. nonparallel
d. all of these
e. none of these
21. Mutagenesis of cells using radiation or a chemicalintercalating agent could be used to create __________ mutations ina region of DNA.
a. random
b. both random and site-specific
c. site-specific
22. In Griffithsâs tranformation experiments, the mice died whenthey were injected with
a. living, no virulent bacteria
b. living, virulent bacteria
c. heat-killed, no virulent bacteria
d. living, nonvirulent bacteria
e. both B and D
23. A monoploid human cells
a. shows only the excessive phenotype of all these genes
b. would be functionally impaired
c. is normal
d. would not survive
24. Gametes containing an abnormal number of chromosomes may occuras a result of
a. paracentric inversion
b. reciprocal translocation
c. disjunction of chromosomes
d. unequal crossing over
25. DNA may be altered as a result of _____________ events thatoccur normally in cells
a. depurination
b. deamination
c. depyrimidation
d. all of the above
e. none of the above
26. Which enzyme prevents DNA from tangling up as the replicationfork migrates during replication?
a. DNA polymerase I
b. DNA helicase
c. topoisonmerase
d. DNA polymerase III
e. DNA gyrase
27. Which of the following enzymes play an important role in DNAreplication?
a. DNA helicase
b. DNA ligase
c. DNA primase
d. all of them
e. DNA polymerase III
28. A mutation gene sustains a mutation that restores the originalphenotype, This is a
a. frame shift mutation
b. transversion
c. reversion
d. transition
e. forward mutation
29. A dicentric chromosome has two
a. telomeres
b. mutations
c. arms
d. centromeres
30. Which type of chromosomal mutation cannot revert to thewild-type state
a. duplication
b. deletion
c. translocation
d. both A and C
e. all of them
31. Translation of histone mRNAs occurs during which phase of theeukaryotic cell cycle?
a. M
b. G1
c. G2
d. S
e. all of these
32. After removal of the RNA primers, Okazaki fragments are joinedthrough a reaction that involves which enzyme?
a. RNA polymerase
b. DNA helicase
c. DNA polymerase
d. DNA primase
e. DNA ligase
33. Which of the following is required for the synthesis of DNAduring replication?
a. DNA polymerase
b. magnesium ions
c. all of them
d. template DNA
e. dNTPs
34. Most of the genome of an active cell consists of
a. heterochromatin
b. histochromatin
c. poluchromatin
d. euchromatin
35. In eukaryotes, DNA replication begins,
a. a single origin of replication on each chromosome
b. a single origin of replication on each chromosome
c. multiple origins of replication on each chromosome
d. all of the above
e. none of the above
36. A human cell contains 2 sets of 24 chromosomes is
a. euploid
b. haploid
c. polyploid
d. aneuploid
37. Pseudodominance occurs as a result of which type ofmutation?
a. translocation
b. duppolication
c. all of these
d. point mutation
e. deletion
38. The enzymatic activity of a telomerase is best described asa
a. none of these
b. polymerase
c. ligase
d. reverse transcriptase
e. topoisomerase
39. A Barr body is an example of
a. constitutive heterochromatin
b. facultative heterochromatin
c. facultative euchromatin
d. constitutive euchromatin
40. An addition or deletion of one or two base pairs in a genecauses a ____________ mutation
a. Transition
b. frameshift
c. nonsense
d. transversion
e. neutral
41. A heterozygous chromosomal inversion can be detected
a. by cytogenetic observation of loops in chromosomes
b. through genetic studies indicating a decrease in the frequencyof recombination between genes
c. by observing a decrease in the number of viable progenyfollowing genetic crosses
d. all of the above
42. The mutagen 5-bromouracil is an analog of which base?
a. adenine
b. threonine
c. thymine
d. cystosine
e. uracil
43. A mutation that changes a codon from one that represents anamino acid to one that signals a chain termination is a______________ mutation.
a. neutral
b. missense
c. frame shift
d. nonsense
44. A chromosomal mutation that results in an increase in theamount of DNA is a(n)
a. duplication
b. inversion
c. deletion
d. both A and C
e. all of the above
45. Prior to replication, the DNA double helix must be untwisted bywhich type of enzyme?
a. topoisomerase
b. ligase
c. polymerase
d. helicase
e. primase
46. In his transformation experiments, Griffiths used cultures ofwhich bacterium?
a. Sacchromyces cerevisiae
b. Escherichia coli
c. Streptococcus pneumoniae.
d. Bacillus cereus
e. Eneterococcus faecalis
47. A mutation changes a codon from a UCG to a UAG. This is a____________ mutation?
a. point
b. nonsense
c. silent
d. both A and B
e. all of the above
48. In eukaryotes, DNA replication
a. is initiated at several sites on chromosomes
b. occurs bidirectional
c. is semidiscontinuous
d. all of the above
e. none of the above
49. Which of the following bacteria are used in the Amestest?
a. Pseudomonas aeruginosa
b. Escherichia coli
c. Vibrio cholera
d. Salmonella typhimurium
e. Rickettsia rickettsii
50. Which of the following changes represents a missensemutation?
a. UGA (stop) to UAG (stop)
b. AAA (lysine) to AGA (arginine)
c. UUU (phenylalanine) to UAA (stop)
d. AUG (methionine) to UGA (stop)
e. AAA (lysine) to AAG (lysine)
1. In Humans, many types of cancers have been linked to?
A. Duplications
B. Inversions
C. translocations
D. deletions
E all of these
2. 5- bromoouracil is mutagenic because it is a(n)
a. base-modifying agent
b. base analog
c. intercalating agent
d. alkylating agent.
3.Ultraviolet radiation creates __________ in DNA
A. 5-methyl cytosine residues
B. breakages
C point mutations
D. mutational hot spots
E thymine dimers
4. The telomeres of chromosomes is composed of
A. heterochromatin
b. nucleosome
c. histone
d. achromatic
5. In eukaryotes, a replicon is
a. the distance between the origin of replication and thetermination of replication
b. a single chromosome
c. the entire genome
d. one DNA strand of a single chromosome
6. In a nonreciprocal interchomosomal translocation, a segment of achromosome is
a. exchanged with an identical segment on a differentchromosome
b. exchanged with an identical segment on a sister chromatid
c. transferred to a different chromosome without a reciprocalexchange of genetic material
d. transferred to a new location on the same chromosome without areciprocal exchange of genetic material
7. Somatic mutations are always.
a. spontaneous
b. carcinogenic
c. heritable
d. lethal
e. none of these
8. A woman with an XO genotype is
a. aneuploid
b. euploid
c. diploid
d. poluploid
9. Spontaneous mutations may occur as a result of
a. all of these
b. errors in DNA replication
c. transposition
d. none of these
e. normal cell biochemistry
10. In the semi conservative model of DNA replication, progenydouble helices consist of
a. one parental DNA strand and one new strand
b. one parental DNA strand and one new RNA strand
c. two new RNA strands
d. two parental DNA strands
e. two new DNA strands
11. A mutation in a gene may alter a cellâs
a. phenotype
b. genotype and phenotype
c. genotype
12. During replication, the direction of synthesis of new DNA fromthe leading strand is
a. both 5â to 3â and 3â to 5â
b. none of these
c. 3â to 5â
d. from left to right only
e. 5â to 3â only
13. A mutation that results in a switch from a purine-pyramidingbase pair to a pyramiding-purine base pair is a _________mutation.
a. neutral
b. transition
c. missense
d. transversion
e. nonsense
14. A trisomic human cell would contain how many chromosomes?
a. 45
b. 46,
c. 47.
d. 48
15. In a strand of DNA, a _____________ bond connects the phosphategroup of one nucleotide to the sugar of the adjacentnucleotide
a. hydrogen
b. ester
c. phosphodiester
d. phosphate
e. disulfide
16. Cri-du-chat syndrome is caused by which type of chromosomalmutation?
a. deletion
b. duplication
c. translocation
d. transversion
e. inversion
17. During replication, the role of DNA primase is to
a. add nucleotide to the growing DNA chain
b. synthesize a short chain for RNA
c. untwist the double helix at the origin of replication
d. relax the super coiling of the double helix
e. synthesize the primo some
18. A(n) ____________ inversion involves the Centro mere
a. chromocentric
b. paracentric
c. epicentric
d. percentric
e. concentric
19. Which of the following substances mutates DNA by intercalatingbetween adjacent base pairs?
a. methyl methane sulfonate
b. all of these
c. nitrous acid
d. 2-amino urine
e. acridine orange
20. A molecule of RNA is always
a. double stranded
b. helical
c. nonparallel
d. all of these
e. none of these
21. Mutagenesis of cells using radiation or a chemicalintercalating agent could be used to create __________ mutations ina region of DNA.
a. random
b. both random and site-specific
c. site-specific
22. In Griffithsâs tranformation experiments, the mice died whenthey were injected with
a. living, no virulent bacteria
b. living, virulent bacteria
c. heat-killed, no virulent bacteria
d. living, nonvirulent bacteria
e. both B and D
23. A monoploid human cells
a. shows only the excessive phenotype of all these genes
b. would be functionally impaired
c. is normal
d. would not survive
24. Gametes containing an abnormal number of chromosomes may occuras a result of
a. paracentric inversion
b. reciprocal translocation
c. disjunction of chromosomes
d. unequal crossing over
25. DNA may be altered as a result of _____________ events thatoccur normally in cells
a. depurination
b. deamination
c. depyrimidation
d. all of the above
e. none of the above
26. Which enzyme prevents DNA from tangling up as the replicationfork migrates during replication?
a. DNA polymerase I
b. DNA helicase
c. topoisonmerase
d. DNA polymerase III
e. DNA gyrase
27. Which of the following enzymes play an important role in DNAreplication?
a. DNA helicase
b. DNA ligase
c. DNA primase
d. all of them
e. DNA polymerase III
28. A mutation gene sustains a mutation that restores the originalphenotype, This is a
a. frame shift mutation
b. transversion
c. reversion
d. transition
e. forward mutation
29. A dicentric chromosome has two
a. telomeres
b. mutations
c. arms
d. centromeres
30. Which type of chromosomal mutation cannot revert to thewild-type state
a. duplication
b. deletion
c. translocation
d. both A and C
e. all of them
31. Translation of histone mRNAs occurs during which phase of theeukaryotic cell cycle?
a. M
b. G1
c. G2
d. S
e. all of these
32. After removal of the RNA primers, Okazaki fragments are joinedthrough a reaction that involves which enzyme?
a. RNA polymerase
b. DNA helicase
c. DNA polymerase
d. DNA primase
e. DNA ligase
33. Which of the following is required for the synthesis of DNAduring replication?
a. DNA polymerase
b. magnesium ions
c. all of them
d. template DNA
e. dNTPs
34. Most of the genome of an active cell consists of
a. heterochromatin
b. histochromatin
c. poluchromatin
d. euchromatin
35. In eukaryotes, DNA replication begins,
a. a single origin of replication on each chromosome
b. a single origin of replication on each chromosome
c. multiple origins of replication on each chromosome
d. all of the above
e. none of the above
36. A human cell contains 2 sets of 24 chromosomes is
a. euploid
b. haploid
c. polyploid
d. aneuploid
37. Pseudodominance occurs as a result of which type ofmutation?
a. translocation
b. duppolication
c. all of these
d. point mutation
e. deletion
38. The enzymatic activity of a telomerase is best described asa
a. none of these
b. polymerase
c. ligase
d. reverse transcriptase
e. topoisomerase
39. A Barr body is an example of
a. constitutive heterochromatin
b. facultative heterochromatin
c. facultative euchromatin
d. constitutive euchromatin
40. An addition or deletion of one or two base pairs in a genecauses a ____________ mutation
a. Transition
b. frameshift
c. nonsense
d. transversion
e. neutral
41. A heterozygous chromosomal inversion can be detected
a. by cytogenetic observation of loops in chromosomes
b. through genetic studies indicating a decrease in the frequencyof recombination between genes
c. by observing a decrease in the number of viable progenyfollowing genetic crosses
d. all of the above
42. The mutagen 5-bromouracil is an analog of which base?
a. adenine
b. threonine
c. thymine
d. cystosine
e. uracil
43. A mutation that changes a codon from one that represents anamino acid to one that signals a chain termination is a______________ mutation.
a. neutral
b. missense
c. frame shift
d. nonsense
44. A chromosomal mutation that results in an increase in theamount of DNA is a(n)
a. duplication
b. inversion
c. deletion
d. both A and C
e. all of the above
45. Prior to replication, the DNA double helix must be untwisted bywhich type of enzyme?
a. topoisomerase
b. ligase
c. polymerase
d. helicase
e. primase
46. In his transformation experiments, Griffiths used cultures ofwhich bacterium?
a. Sacchromyces cerevisiae
b. Escherichia coli
c. Streptococcus pneumoniae.
d. Bacillus cereus
e. Eneterococcus faecalis
47. A mutation changes a codon from a UCG to a UAG. This is a____________ mutation?
a. point
b. nonsense
c. silent
d. both A and B
e. all of the above
48. In eukaryotes, DNA replication
a. is initiated at several sites on chromosomes
b. occurs bidirectional
c. is semidiscontinuous
d. all of the above
e. none of the above
49. Which of the following bacteria are used in the Amestest?
a. Pseudomonas aeruginosa
b. Escherichia coli
c. Vibrio cholera
d. Salmonella typhimurium
e. Rickettsia rickettsii
50. Which of the following changes represents a missensemutation?
a. UGA (stop) to UAG (stop)
b. AAA (lysine) to AGA (arginine)
c. UUU (phenylalanine) to UAA (stop)
d. AUG (methionine) to UGA (stop)
e. AAA (lysine) to AAG (lysine)
