BIO 110 CSM Test 4

RNA synthesis is also known as: A) elongation. B) reverse transcription. C) termination. D) translation E) transcription.

E) transcription.

What type(s) of RNA makes up a portion of the ribosome? A) mRNA B) rRNA C) tRNA D) There is no RNA in a ribosome E) all three kinds of RNA

B) rRNA

In replication, once the DNA strands have been separated, reformation of the double helix is prevented by: A) DNA helicase enzyme. B) single-strand binding proteins. C) DNA polymerases. D) ATP. E) GTP.

B) single-strand binding proteins.

Which of the following nucleotide sequences represents the complement to the DNA strand 5' -AGATCCG- 3' ? A) 5' -AGATCCG- 3' B) 3' -AGATCCG- 5' C) 5' -CTCGAAT- 3' D) 3' -CTCGAAT- 5' E) 3' -TCTAGGC- 5'

E) 3' -TCTAGGC- 5'

The total number of different three-base combinations of the four nucleic acid bases is: A) 12 B) 16 C) 20 D) 64 E) 256

D) 64

Which of the following statements about DNA is FALSE? A) DNA is capable of forming many different sequences. B) DNA contains thymine instead of uracil. C) DNA is double-stranded rather than single-stranded. D) DNA is only found in eukaryotic cells. E) DNA contains the sugar deoxyribose.

D) DNA is only found in eukaryotic cells.

How is a single strand of DNA able to serve as a template for the synthesis of another strand? A) Nucleotides pair with those of the original strand to form a new strand. B) Hydrogen bonds holding the two strands together are easy to break, allowing one strand to be a template. C) A single strand of DNA is not able to serve as a template. D) One strand of DNA directs the synthesis of a new strand on its partner. E) Both the pairing of nucleotides and the breaking of hydrogen bonds.

E) Both the pairing of nucleotides and the breaking of hydrogen bonds.

RNA DIFFERS from DNA in all of the following EXCEPT: A) RNA is usually single-standed. B) RNA lacks thymine. C) RNA contains uracil. D) RNA contains ribose. E) RNA contains cytosine.

E) RNA contains cytosine.

Two chains of DNA must run in __________ direction(s) and must be __________ if they are to bond with each other. A) the same; uncomplementary B) opposite; uncomplementary C) parallel; uncomplementary D) parallel; complementary E) antiparallel; complementary

E) antiparallel; complementary

Which of the following is made from DNA? A) tRNA only B) mRNA only C) rRNA only D) mRNA and tRNA only E) mRNA, tRNA, and rRNA

E) mRNA, tRNA, and rRNA

Which of the following adds new nucleotides to a growing DNA chain? A) DNA polymerase B) DNA helicase C) RNA primer D) primase E) RNA polymerase

A) DNA polymerase

Which of the following statements concerning nucleotide excision repair is FALSE? A) It is a type of mismatch repair. B) It involves a nuclease. C) It involves a DNA polymerase. D) It involves DNA ligase. E) It is implicated in xeroderma pigmentosum.

A) It is a type of mismatch repair.

A gene can be defined as: A) a DNA sequence that carries information to produce a specific RNA or protein product. B) a DNA nucleotide sequence that carries information to produce a specific polypeptide. C) a DNA or RNA sequence that carries information to produce a single polypeptide. D) a DNA nucleotide sequence that carries information to produce an enzyme. E) a DNA or RNA sequence that carries information to produce a specific polypeptide.

A) a DNA sequence that carries information to produce a specific RNA or protein product.

Transfer RNA carries __________ to the mRNA. A) amino acids B) nucleic acids C) genes D) codons E) nucleotides

A) amino acids

During protein synthesis, ribosomes: A) attach to the mRNA molecule and travel along its length. B) attach to the DNA molecule and travel along its length to produce an mRNA molecule. C) translate mRNA into tRNA. D) transcribe mRNA to tRNA. E) translate mRNA into DNA.

A) attach to the mRNA molecule and travel along its length.

In DNA replication, the lagging strand: A) is synthesized as a series of Okazaki fragments. B) is synthesized as a complementary copy of the leading strand. C) pairs with the leading strand by complementary base pairing. D) is made up entirely of RNA primers. E) is not synthesized until the synthesis of the leading strand is completed.

A) is synthesized as a series of Okazaki fragments.

The codon is found in the: A) mRNA. B) nontemplate strand of DNA. C) template strand of DNA. D) tRNA. E) rRNA.

A) mRNA.

Substitution of one base pair for another can result in a __________ mutation that results in the conversion of an amino acid specifying codon to a termination codon. A) nonsense B) frameshift C) chromosomal D) missense E) silent

A) nonsense

In essentially all organisms, the AUG codon codes for: A) the initiation of translation. B) the termination of transcription. C) the termination of chain elongation. D) the amino acid valine. E) a termination tRNA molecule.

A) the initiation of translation.

Enzymes called __________ form breaks in the DNA molecules to prevent the formation of knots in the DNA helix during replication. A) topoisomerases B) single-strand binding proteins C) DNA polymerases D) RNA polymerases E) DNA ligases

A) topoisomerases

What is the mRNA sequence for a strand of DNA reading 5'-CCGTACT-3'? A) 5' GGCAUGA 3' B) 3' GGCAUGA 5' C) 5' GGCATGA 3' D) 3' GGCATGA 5'

B) 3' GGCAUGA 5'

Which of the following best describes semiconservative replication? A) The translation of a DNA molecule into a complementary strand of RNA. B) A DNA molecule consists of one parental strand and one new strand. C) The number of DNA molecules is doubled with every other replication. D) The replication of DNA never takes place with 100% accuracy. E) The replication of DNA takes place at a defined period in the cell cycle.

B) A DNA molecule consists of one parental strand and one new strand.

Why is only one strand of DNA transcribed into mRNA? A) Because mRNA is only required in small quantities. B) Because transcribing both DNA strands would produce different amino acid sequences. C) Because the other strand would produce the same amino acid sequence in reverse order. D) Because all genes are located on the same DNA strand, while the other strand acts as protection E) Because the other strand is transcribed directly into amino acids.

B) Because transcribing both DNA strands would produce different amino acid sequences.

Which of the following causes the unwinding of the DNA double helix? A) DNA polymerase B) DNA helicase C) RNA primer D) primosome E) RNA polymerase

B) DNA helicase

Okazaki fragments are joined together by: A) RNA polymerase. B) DNA ligase. C) DNA polymerase. D) RNA ligase. E) primase.

B) DNA ligase.

__________, the ends of eukaryotic chromosomes, shorten with every cell replication event. A) Centromeres B) Telomeres C) Kinetochores D) Primosomes E) Nucleosomes

B) Telomeres

How is the 4-letter language of nucleic acids converted into the 20-word language of amino acids? A) The 4 nucleic acid bases combine in 2-letter combinations that define different amino acids. B) The 4 nucleic acid bases combine in 3-letter sequences that define different amino acids. C) Triplets of the 2-letter nucleic acid bases are translated into the 20 different amino acids. D) The 4 bases each specify 1 amino acid, which give rise to the remaining 16 amino acids. E) The 4 bases are first converted into tRNA molecules, which can each attach to 5 amino acids.

B) The 4 nucleic acid bases combine in 3-letter sequences that define different amino acids.

__________ determined the structure of the molecule DNA. A) Crick and Wilkins B) Watson and Crick C) Franklin and Crick D) Franklin E) Watson, Crick, and Wilkins

B) Watson and Crick

Where is the amino-acid binding site located on the tRNA molecule? A) in the middle of the loop B) at the end of the 3' end of the molecule C) in the first loop D) along the longest stretch of base pairing in the molecule E) on the 5' end of the molecule

B) at the end of the 3' end of the molecule

One of the mRNA codons specifying the amino acid leucine is 5'-CUA-3'. Its corresponding anticodon is: A) 5'-GAT-3' B) 3'-AUC-5' C) 3'-GAU-5' D) 3'-GAT-5' E) 5'-GAU-3'

C) 3'-GAU-5'

Hydrogen bonds can form between guanine and __________, and between adenine and __________. A) phosphate; sugar B) thymine; cytosine C) cytosine; thymine D) sugar; phosphate E) adenine; guanine

C) cytosine; thymine

The DNA strand that is replicated smoothly and continuously is called the: A) primary strand. B) first strand. C) leading strand. D) alpha strand. E) lagging strand.

C) leading strand.

Frameshift mutations result from: A) the substitution of one base pair for another. B) the substitution of more than one base pair. C) the insertion or deletion of one or two base pairs. D) the substitution of a stop codon for an amino acid-specifying codon. E) the substitution of a start codon for an amino acid codon.

C) the insertion or deletion of one or two base pairs.

When a DNA molecule containing a wrong base at one location in one strand is replicated: A) the mutation is corrected by the DNA polymerase enzyme. B) the mutation is ignored by the DNA polymerase enzyme. C) the mutation is copied into one of the two daughter molecules. D) the mutation is copied into both of the daughter molecules. E) the replication is stopped.

C) the mutation is copied into one of the two daughter molecules.

Interrupted coding sequences include long sequences of bases that do not code for amino acids. These noncoding sequences, called __________, are found in __________ cells. A) exons; only prokaryotic B) introns; only prokaryotic C) exons; only eukaryotic D) introns; only eukaryotic E) exons; both prokaryotic and eukaryotic

D) introns; only eukaryotic

Primase is the enzyme responsible for: A) unwinding the DNA double strand to allow DNA polymerase access to the template DNA. B) introducing nicks into the DNA double strand in order to prevent the formation of knots. C) hydrolyzing ATP to facilitate DNA unwinding. D) making short strands of RNA at the site of replication initiation. E) forming a replication fork in the DNA double helix.

D) making short strands of RNA at the site of replication initiation.

A mutation that replaces one amino acid in a protein with another is called a __________ mutation. A) frameshift B) recombinant C) nonsense D) missense E) neutral

D) missense

The information carried by DNA is incorporated in a code specified by the: A) phosphodiester bonds of the DNA strand. B) number of separate strands of DNA. C) size of a particular chromosome. D) specific nucleotide sequence of the DNA molecule. E) number of bases in a DNA strand.

D) specific nucleotide sequence of the DNA molecule.

The final product of DNA replication is: A) mRNA, tRNA, and rRNA molecules. B) a wide variety of proteins. C) DNA fragments. D) two DNA molecules, each of which contains one new and one old DNA strand. E) the enzymes needed for further processes, such as DNA polymerase.

D) two DNA molecules, each of which contains one new and one old DNA strand.

Adenine forms a complementary pair with __________ in RNA and __________ in DNA. A) adenine; thymine B) thymine; adenine C) thymine; thymine D) uracil; thymine E) thymine; uracil

D) uracil; thymine