chapter 5

UV radiation can result in __________ in a cell's DNA. A. silent mutation B. frameshift mutation C. nonsense mutation D. thymine dimers

D. thymine dimers

During DNA replication, which enzyme is involved in proofreading to prevent the incorrect matching of nucleotides? A. helicase B. DNA polymerase C. primase D. ligase

B. DNA polymerase

Primase lays down a short piece of __________ as a primer to start DNA replication. A. DNA B. RNA C. carbohydrate D. protein

B. RNA

The role of transcription factors is to signal __________. A. DNA polymerase to the promoter region of the intended gene to be transcribed B. RNA polymerase to the promoter region of the intended gene to be transcribed C. the ribosome formation around the mRNA D. the reverse transcriptase to the promoter region of the intended gene to be transcribed

B. RNA polymerase to the promoter region of the intended gene to be transcribed

Genes can be silenced by a process called DNA methylation. Which of the following compounds is a methyl group? A. CH3 B. CO2 C. COOH D. OH

A. CH3

Which of the following would be considered a FALSE statement about small noncoding RNAs? A. They are found only in prokaryotic cells. B. They can be used to tag a ribosome to be destroyed. C. They are used in post-transcription regulation. D. They reduce the amount of protein made from mRNA.

A. They are found only in prokaryotic cells.

Of the following statements, which one is NOT related to transposable elements? A. They create a stable, non-changing genome. B. They recombine the genome. C. They require the transposase enzyme. D. They can change the rate of gene expression.

A. They create a stable, non-changing genome.

In an inducible operon, what protein is used to turn off transcription by binding to the operator sequence? A. a repressor protein B. an inducible protein C. post-transcription protein D. an initiator protein

A. a repressor protein

A transposon that relies on an RNA intermediate is called __________. A. a retrotransposon B. RNA polymerase C. an RNA dependent transposon D. a reverse transcriptase

A. a retrotransposon

In DNA replication, protein factors are more heavily required for replication in __________. A. eukaryotic cells B. prokaryotic cells C. both eukaryotic and prokaryotic cells D. in neither eukaryotic nor prokaryotic cells.

A. eukaryotic cells

The process of removing incorrect nucleotides and replacing them with correct ones is referred to as __________. A. excision repair B. mutation correction C. replication repair D. base substitution

A. excision repair

Which of the following mutations is the most detrimental to the cell? A. frameshift mutation B. nonsense mutation C. silent mutation D. missense mutation

A. frameshift mutation

One major difference between prokaryotic and eukaryotic translation is __________. A. prokaryotic translation is polycistronic, and eukaryotic translation is almost always monocistronic. B. prokaryotic translation involves three types of RNA, while eukaryotic translation involves two types of RNA C. prokaryotic translation requires more protein factors than eukaryotic translation D. prokaryotic translation involves polysomes, while eukaryotic translation does not

A. prokaryotic translation is polycistronic, and eukaryotic translation is almost always monocistronic.

cDNA is a product of the action of __________. A. reverse transcriptase B. RNA polymerase C. DNA polymerase D. transferase

A. reverse transcriptase

In DNA replication, Okazaki fragments are required in synthesizing __________. A. the lagging strand, because the DNA polymerase can move only in the 5' to 3' direction B. the leading strand, because the DNA polymerase can move only in the 5' to 3' direction C. the origin of replication D. both strands, because the fragments provide a starting point for DNA polymerase

A. the lagging strand, because the DNA polymerase can move only in the 5' to 3' direction

Griffith's experiment proved that bacteria can take up naked DNA from the environment and use it as part of their genome. This process, which can occur in a laboratory or in a natural setting, is called __________. A. transformation B. transposition C. transduction D. conjugation

A. transformation

Which of the following is considered a pre-transcriptional regulation and NOT a post-transcriptional regulation? A. the rate of ribosome association with the mRNA B. a repressed operon C. messenger RNA stability D. the rate of mRNA processing in eukaryotic cells

B. a repressed operon

The term "redundancy" in molecular biology refers to __________. A. repressing the expression of a gene B. different codons that code for the same amino acid C. overexpression of a gene D. the multiple sites to begin DNA replication

B. different codons that code for the same amino acid

The genetic makeup of an organism is its __________. A. chromosome B. genotype C. phenotype D. karyotype

B. genotype

The Ames test is used to identify if a chemical will result in mutations. This test uses the microorganism S. typhimurium and the amino acid __________. A. proline B. histidine C. lysine D. glycine

B. histidine

In eukaryotic mRNA, there are sequences of mRNA that do NOT encode for specific amino acids and do NOT contribute to the protein. These sequences are called __________. A. promoters B. introns C. Okazaki fragments D. exons

B. introns

Riboswitches are best defined as __________. A. parts of mRNA that are not translated and act as pre-transcription regulators B. parts of mRNA that are not translated and act as post-transcription regulators C. factors that block the ribosome from binding D. parts of mRNA that block the first tRNA from entering into the "A" site of the ribosome

B. parts of mRNA that are not translated and act as post-transcription regulators

A codon consists of __________ nucleotides. A. two B. three C. four D. five

B. three

Proteins provide cells with the necessary equipment to perform normal cellular activity. Without gene expression the cell __________. A. could function with minimal capabilities B. would die C. would still be able to metabolize substrates D. would still be able to reproduce

B. would die

What is the main enzyme required for transcription of a gene? A. DNA polymerase B. DNA gyrase C. RNA polymerase D. helicase

C. RNA polymerase

If a cell is to be transformed in a lab, the cell must be __________ to uptake the available genetic information. A. killed B. exposed to a virus C. competent D. equipped with a pilus

C. competent

The exchange of genetic information by use of a pilus and cell-to-cell interaction is called __________. A. transformation B. transduction C. conjugation D. transposons

C. conjugation

During optimum conditions, E. coli will replicate every 20 minutes. Because the genes required for replication are needed as part of a routine function, these genes are considered __________. A. operator genes B. repressible genes C. constitutive genes D. facultative genes

C. constitutive genes

Where is the chromosomal DNA found in prokaryotic cells? A. ribosome B. nucleus C. nucleoid D. nucleolus

C. nucleoid

To start DNA replication, the origin of replication is recognized by a collection of factors called the __________. A. single-strand binding proteins B. RNA primer C. primosome D. Okazaki fragments

C. primosome

RNA nucleotides are made of a sugar, a phosphate, and a nitrogen base. Which sugar is unique to RNA nucleotides and NOT found in DNA nucleotides? A. fructose B. deoxyribose C. ribose D. glucose

C. ribose

There are two nonstandard encoding amino acids: __________. A. cysteine and lysine B. methionine and leucine C. selenocysteine and pyrrolysine D. proline and glycine

C. selenocysteine and pyrrolysine

Transduction that involves a temperate phage integrating into the host cell genome is called __________. A. generalized transduction B. localized transduction C. specialized transduction D. exchange transduction

C. specialized transduction

Which type of RNA carries in amino acids and adds the amino acids to the "A" site in the ribosome? A. cRNA B. rRNA C. tRNA D. mRNA

C. tRNA

Which of the following nucleotides is found only in RNA and not in DNA? A. cytosine B. adenine C. uracil D. guanine

C. uracil

RNA primers are removed from the leading and lagging strand by __________. A. helicase B. DNA polymerase III C. topoisomerase. D. DNA polymerase I

D. DNA polymerase I

In DNA replication, what is the main enzyme responsible for adding complementary nucleotides to the daughter strand while reading the parent strand? A. primase B. DNA polymerase I C. gyrase D. DNA polymerase III

D. DNA polymerase III

Which enzyme is the main contributor to the development of spontaneous mutations? A. ligase B. RNA primase. C. helicase D. DNA polymerase III

D. DNA polymerase III

Of the following statements, which does NOT apply to a microorganism that has a fertility plasmid? A. It can undergo horizontal gene transfer. B. It has a pilus. C. It can further develop into a Hfr cell. D. It can undergo vertical gene transfer.

D. It can undergo vertical gene transfer.

Which of the following statements is NOT a characteristic of plasmids? A. Plasmids are involved in horizontal gene transfer. B. Plasmids carry genes that may be involved in antibiotic resistance. C. Plasmids replicate independently of the cell's chromosome. D. Plasmids are part of the cell's chromosome.

D. Plasmids are part of the cell's chromosome.

After translation, protein modifications are necessary for a final functioning product. Which of the following is NOT part of protein modification? A. trimming B. addition of organic compounds C. addition of inorganic factors D. addition of a methionine

D. addition of a methionine

Quorum sensing allows bacteria within communities to communicate with chemical messages, which may help regulate gene expression. The chemical messages are called __________. A. autoregulators B. autofactors C. autorepressors D. autoinducers

D. autoinducers

The process of transferring of genetic information between cells in the same generation is referred to as __________. A. asexual reproduction B. sexual reproduction C. vertical gene transfer D. horizontal gene transfer

D. horizontal gene transfer

Which functional group is found at the 5' end of DNA? A. methyl group B. hydroxyl group C. carboxyl group D. phosphate group

D. phosphate group

Which type of genetic material may be found in both prokaryotic and eukaryotic cells and may contain genes conferring antibiotic resistance? A. chloroplast DNA B. chromosomal DNA C. mitochondrial DNA D. plasmids

D. plasmids

An anticodon is found on __________. A. mRNA B. DNA C. rRNA D. tRNA

D. tRNA

The term used by molecular biologists to describe the flow of genetic information from DNA, to RNA, to protein is __________. A. transcription B. gene expression C. translation D. the central dogma of biology

D. the central dogma of biology