55 terms


1) All of the following are associated with nucleic acid structure EXCEPT
A) ribose.
B) hydrogen bonds.
C) uracil.
D) ionic bonds.
E) phosphate.
2) Which of the following is found at the 5 end of a DNA strand?
A) a phosphate group
B) a hydrogen bond
C) a hydroxyl group
D) histones
E) a methyl group
3) The bacterial chromosome is
A) usually circular.
B) found in a nucleoid.
C) found in a nucleus.
D) both circular and found in a nucleoid.
E) both circular and found in a nucleus.
4) Which of the following types of plasmids allows a bacterial cell to kill its competitors?
A) virulence factors
B) fertility factors
C) bacteriocin factors
D) resistance factors
E) cryptic plasmids
5) Which of the following is NOT involved the packaging of eukaryotic chromosomes?
A) nucleosomes
B) histones
C) heterochromatin
D) euchromatin
E) Okazaki fragments
6) Which of the following statements is true of bacterial plasmids?
A) They are found in the nucleoid.
B) They can replicate autonomously.
C) They carry genes for essential metabolic functions.
D) They are small circular DNA molecules.
E) They are small circular DNA molecules that can replicate autonomously.
7) DNA helicases
A) break hydrogen bonds between complementary nucleotides.
B) synthesize short DNA molecules important for the function of DNA polymerase.
C) seal gaps between DNA fragments.
D) proofread DNA molecules.
E) assist in recognition of promoters during transcription.
8) Which of the following statements concerning transcription in bacteria is FALSE?
A) It occurs in the nucleoid region.
B) Sigma factors are parts of RNA polymerase that recognize promoter regions.
C) The same RNA polymerase transcribes primer RNA, mRNA, tRNA, and rRNA.
D) Termination is either self-induced or due to the presence of Rho protein.
E) There are a variety of sigma factors that affect transcription.
9) Which of the following is involved in translation?
D) both mRNA and tRNA
E) mRNA, rRNA and tRNA are all involved.
10) Which of the following is a characteristic shared by DNA and RNA polymerases?
A) efficiency of proofreading
B) type of nucleotides used
C) direction of polymerization
D) speed
E) dependence on helicase
11) Which of the following is the strongest base pair?
A) guanine-cytosine
B) adenine-uracil
C) adenine-thymine
D) guanine-thymine
E) both adenine-uracil and adenine-thymine
12) A codon is a particular combination of three nucleotides. Therefore, there are __________ possible combinations of the nucleotides A, C, G, and T.
A) 16
B) 4
C) 12
D) 64
E) 32
13) The AUG codon functions in coding for the amino acid methionine and as a
A) termination signal.
B) start signal.
C) "wobble" codon.
D) marker for introns.
E) recognition site for RNA polymerase
14) Which of the following must be removed from a eukaryotic mRNA molecule before it can be translated?
A) promoter
B) exon
C) intron
D) anticodon
E) codon
15) A charged tRNA first enters the ribosomal __________ site and then moves into the __________ site.
A) A, E
B) P, A
C) P, E
D) A, P
E) E, A
16) Which of the following statements regarding eukaryotic transcription is FALSE?
A) Transcription occurs in the nucleus, mitochondria, and chloroplasts (if present).
B) Multiple transcription factors are required.
C) There are four different RNA polymerases.
D) Multiple elongation factors are required.
E) A guanine is added to the 3 end, and a poly-A tail is added to the 5 end of the mRNA transcript.
17) Semiconservative DNA replication means that
A) each daughter DNA molecule is composed of one original strand and one new strand.
B) nucleotides are constantly being recycled as cells make DNA.
C) the cell can proofread its newly synthesized DNA only part of the time.
D) the sequence of a DNA molecule is preserved as it is being replicated.
E) each strand of a double-stranded DNA molecule is replicated differently.
18) Which of the following is NOT a characteristic of Okazaki fragments?
A) They are checked for accuracy by DNA polymerase III.
B) They make up the lagging strand of replicated DNA.
C) They begin with an RNA primer.
D) They are joined together by DNA ligase.
E) They are longer in eukaryotic cells.
19) The proofreading function of DNA polymerase III results in an error rate of __________ during DNA replication.
A) 1 error in 1,000 bases
B) 1 error in 100,000 bases
C) 1 error in 1 million bases
D) 1 error in 10 million bases
E) 1 error in 10 billion bases
20) Which of the following processes is involved in the "central dogma" of genetics?
A) translation
B) transcription
C) DNA replication
D) transcription and translation
E) DNA replication and translation
21) Inducible operons
A) are active in the presence of a repressor.
B) are generally anabolic pathways.
C) are normally active.
D) usually require an activator to be transcribed.
E) usually require a repressor to be transcribed.
22) Which of the following are considered to be frameshift mutations?
A) insertions
B) inversions
C) deletions
D) both inversion and insertions
E) both deletions and insertions
23) If the codon AAA is changed to AAG, it still codes for the amino acid lysine; this is an example of a
A) silent mutation.
B) nonsense mutation.
C) frameshift mutation.
D) gross mutation.
E) missense mutation.
24) Which of the following causes mutations by creating thymine dimers?
A) nucleotide analogs
B) nitrous acid
C) ultraviolet light
D) benzopyrene
E) gamma rays
25) DNA damage caused by ethidium bromide results in __________ mutations.
A) insertion
B) substitution
C) deletion
D) both inversion and insertion
E) both insertion and deletion
26) Which of the following is a DNA repair enzyme activated by visible light?
A) transposase
B) DNA photolyase
C) bacteriocin
D) DNA ligase
E) primase
27) The Ames test proves that a chemical is
A) carcinogenic.
B) carcinogenic in Salmonella.
C) mutagenic in Salmonella.
D) carcinogenic in humans.
E) mutagenic in humans.
28) The horizontal transfer process known as transduction
A) involves a virus.
B) requires a pilus.
C) requires a cell to be "competent."
D) requires a plasmid.
E) involves a mutagen.
29) Frederick Griffith discovered
A) transformation.
B) transposons.
C) the lac operon.
E) conjugation.
30) In conjugation, F+ cells
A) serve as recipient cells.
B) contain an F plasmid.
C) do not have conjugation pili.
D) can transfer DNA only to other F+ cells.
E) contain "jumping genes."
31) Another term for the palindromic sequence found at the ends of transposons is a(n)
A) complex transposon.
B) bacteriophage.
C) insertion sequence.
D) inverted repeat.
E) transposase.
32) Which of the following is characteristic of prokaryotic genomes but NOT eukaryotic genomes?
A) histones
B) circular chromosomes
C) linear chromosomes
D) enclosed in a nuclear membrane
E) typically consist of a few to several chromosomes
33) Genes are active in a region of the eukaryotic chromosome called
A) heterochromatin.
B) the histone.
C) the nucleoid.
D) the plasmid.
E) euchromatin.
34) The energy required for DNA replication comes from
A) DNA polymerase.
B) triphosphate deoxyribonucleotides.
C) DNA ligase.
D) RNA primer.
E) the leading strand.
35) Which of the following is NOT involved in the regulation of the lac operon?
A) an inducer
B) a repressor protein
C) an iRNA
D) glucose
E) cyclic AMP
36) Genetic elements known as promoters are initiation points in the process of
A) DNA replication.
B) transcription.
C) translation.
D) mutation repair.
E) transformation.
37) Codons are recognized during
A) translation.
B) transcription.
C) base excision.
D) DNA replication.
E) transduction.
38) __________ is initiated at sequences called origins.
A) DNA replication
B) Translation
C) Splicing
D) Transcription
E) Transposition
39) The process of __________ requires the activity of DNA ligase.
A) translation
B) capping
C) transcription
D) DNA replication
E) transduction
40) RNA polymerase is primarily responsible for
A) DNA replication.
B) translation.
C) transcription.
D) transformation.
E) polyadenylation.
41) The process of __________ requires participation of tRNA molecules.
A) DNA replication
B) capping
C) transcription
D) translation
E) dark repair
42) The process of __________ is initiated with the incorporation of fMet.
A) translation
B) transcription
C) capping
D) DNA replication
E) light repair
43) Initiation of __________ involves Sigma factor molecules.
A) DNA replication
B) translation
C) transcription
D) splicing
E) termination
44) The process of __________ is described as semiconservative.
A) translation
B) transcription
C) mismatch repair
D) transformation
E) DNA replication
45) During __________, the growing polymer is located in the P site.
A) polyadenylation
B) DNA replication
C) mismatch repair
D) transcription
E) translation
1) Prokaryotic cells are diploid.
2) Prokaryotes have one type of DNA polymerase, which is different from that of eukaryotes.
3) The most common type of mutation is a point mutation.
4) Most bacteria have a natural ability to take up DNA from their environment.
5) The structure of DNA explains both its ability to encode genetic information and the way in which it is copied during cell reproduction.
6) DNA, which is negatively charged, wraps around positively charged histones as part of the packaging of eukaryotic chromosomes.
7) Bidirectional replication means that each strand of a DNA molecule is replicated in the opposite direction from the other.
8) The phenotype of an organism reflects only part of its genotype.
9) In generalized transduction, viruses carry random DNA sequences from one cell to another.
10) DNA polymerase III participates in the dark repair mechanism of DNA mutation repair.