Nucleic Acids and Protein Synthesis Exam Questions Ch.22 4e

General, Organic and Biological Chemistry, 4e (Smith)

Chapter 22 Nucleic Acids and Protein Synthesis

1) Which component is not part of a nucleotide?

A) A nitrogen-containing base

B) A monosaccharide

C) An amino acid

D) A phosphate group

2) Which base is found in DNA or RNA, but not both?

A) Uracil

B) Cytosine

C) Adenine

D) Guanine

3) Which choice is a polynucleotide that is a polymer of ribonucleotides?

A) DNA

B) RNA

C) Both DNA and RNA

D) Neither DNA nor RNA

4) What is the name of the nucleoside shown?

A) Hydroadenine

B) Deoxyadenosine

C) Deoxyguanosine

D) Hydroguanine

5) What is the base present in the nucleoside below?

A) Purine

B) Pyrimidine

C) Phenol

D) Aniline

6) What is the name of the nucleoside shown?

A) Uridine

B) Uridosine

C) Oxyuridine

D) Oxyuridosine

7) Which nucleotide abbreviation is not valid?

A) dAMP

B) AMP

C) dUMP

D) CMP

8) Which of the following is the name of the nucleoside formed from D-ribose and cytosine?

A) Ribosine

B) Cytose

C) Cytidine

D) Cytamine

9) Which structure represents a nucleotide?

A)

B)

C)

D)

10) What is a nucleoside?

A) A monosaccharide + a base

B) A polymer of ribonucleotides

C) The monosaccharides ribose and deoxyribose

D) A monosaccharide + a base + phosphate

11) The combination of a monosaccharide like ribose or deoxyribose, a base like purine or pyrimidine, and a phosphate unit is called ________.

A) a polysaccharide

B) a nucleoside

C) a nucleotide

D) a polyamide

12) What is the abbreviation of the structure shown below?

A) GMP

B) AMP

C) CMP

D) TMP

13) Which is the structure of ATP?

A)

B)

C)

D)

14) A polynucleotide contains ________.

A) one free phosphate group at the 5' end

B) a backbone of alternating sugar and base groups

C) one free phosphate group at the 1' end

D) one free OH group at the 5' end

15) What is the abbreviation of the polynucleotide shown?

A) TAC

B) CAT

C) CGT

D) TGC

16) Which base is at the 3' end of the structure shown?

A) Adenine

B) Cytosine

C) Guanine

D) Thymine

E) Uracil

17) Which base is at the 5' end of the structure shown?

A) Adenine

B) Cytosine

C) Guanine

D) Thymine

E) Uracil

18) Which sequence has a purine base at the 3' end?

A) TCTAG

B) AUCCT

C) GUGCCU

D) CCTTC

19) Which sequence is not possible?

A) GAGAA

B) TAGGG

C) UTAGA

D) CCCCC

20) How many different trinucleotides can be formed from one guanine, one uracil, and one adenine?

A) 1

B) 3

C) 6

D) 18

E) 27

21) How many hydrogen bonds form between a G–C base pair in a DNA double helix?

A) 1

B) 2

C) 3

D) 4

22) What is the complementary strand for the DNA strand 5'–AAGGTAGC–3'?

A) 3'–CGATGGAA–5'

B) 3'–AAGGTAGC–5'

C) 3'–TTCCATCG–5'

D) 5'–TTCCATCG–3'

E) 5'–CGATGGAA–3'

23) What is the process by which DNA makes a copy of itself when a cell divides?

A) Transcription

B) Replication

C) Duplication

D) Cloning

24) What step in the synthesis of proteins involves the genetic message contained in mRNA specifying the specific amino acid sequence of a protein?

A) Elongation

B) Directed synthesis

C) Translation

D) Protein hydrolysis

25) Which statement concerning the replication of DNA is not true?

A) The first step in replication is unwinding the DNA to expose the bases on each strand.

B) A new phosphodiester bond is formed between the 5'-phosphate of the nucleoside triphosphate and the 3'-OH group of the new DNA strand.

C) Replication occurs in only one direction on the template strand, from the 5' end to the 3' end.

D) In replication, the lagging strand is synthesized in small fragments which are then joined together by a DNA ligase enzyme.

26) Which is not a type of RNA molecule?

A) mRNA

B) dRNA

C) tRNA

D) rRNA

27) Which is the smallest type of RNA?

A) mRNA

B) dRNA

C) tRNA

D) rRNA

28) Which statement about RNA codons is not true?

A) It is possible for two different codons to code for the same amino acid.

B) There are 64 different codons.

C) Three codons are "stop" codons, signaling the termination of protein synthesis.

D) Three codons are "start" codons, signaling the start of protein synthesis.

29) Which is not one of the three stages in translation?

A) Termination

B) Initiation

C) Elongation

D) Mutation

30) Which amino acid sequence is coded for by the mRNA sequence 5' AAG GCU AGU GGC 3'?

A) Thr–His–Asn–Asp

B) Lys–Ala–Ser–Gly

C) Asp–Asn–His–Thr

D) Gly–Ser–Ala–Lys

31) Which amino acid sequence is coded for by the mRNA sequence 5' CCA AAC UGG GUA 3'?

A) Pro-Asn-Trp-Val

B) Gln-Lys-Cys-Asp

C) Pro-Ser-Tyr-Val

D) Leu-Ile-Leu-Asp

32) Which mRNA sequence codes for the amino acid sequence Leu–Gly–Asp–Arg?

A) 5' CUA GGU GAU AGC 3'

B) 5' CUA CAG GAU AGA 3'

C) 5' AGA GAU GGA UUA 3'

D) 5' UUA GGA GAU AGA 3'

33) Which codon does not code for alanine?

A) GCG

B) GCU

C) GCC

D) GCA

E) GAC

34) Which is not a stop codon?

A) UAA

B) UGA

C) UAG

D) UGC

35) Each individual tRNA contains ________.

A) a base sequence that is identical to the informational strand of DNA

B) the sequence of codons that determines the order of amino acids in the protein

C) an anticodon of three nucleotides that is complementary to the codon in mRNA and identifies individual amino acids

D) an anticodon complementary to any of the three stop codons

36) What polypeptide would be synthesized from the following template strand of DNA:

3' CGG AGA CGG ACG 5'?

A) Ala–Ser–Ala–Cys

B) Arg–Arg–Arg–Cys

C) Gln–Lys–Gln–Met

D) Ala–Ser–Ala–Thr

E) Cys–Ala–Ser–Ala

37) Which type of mutation occurs when a DNA sequence changes from

GGA TCA CCG GAA…. to GGA TCC CGG….?

A) A deletion mutation

B) An insertion mutation

C) A point mutation

D) A transcription mutation

38) A DNA sequence segment is initially AAA ATG TGA CCC. Which mutation would have the most significant effect on the resultant protein synthesized?

A) AAG ATG TGA CCC

B) AAA ATT TGA CCC

C) AAA ATG GAC CCU

D) AAA ATG TGA CGC

39) A DNA sequence segment is initially AAA ATG TGA CCC. Which mutation would have the least effect on the resultant protein synthesized?

A) AAG ATG TGA CCC

B) AAA ATT TGA CCC

C) AAA ATG GAC CCU

D) AAA ATG TGA CGC

40) Which is a genetic disease?

A) Tay-Sachs disease

B) Sickle cell anemia

C) Galactosemia

D) Huntington's disease

E) All of the diseases are genetic diseases.

41) How many different mRNA sequences code for the dipeptide Leu–Ile?

A) 1

B) 2

C) 9

D) 18

42) Which is not one of the elements needed to amplify DNA by polymerase chain reaction (PCR)?

A) Two primers—short polynucleotides that are complementary to the two ends of the segment to be amplified

B) A restriction endonuclease enzyme that cleaves DNA at specific locations

C) The segment of DNA that must be copied

D) A DNA polymerase enzyme that will catalyze the synthesis of a complementary strand of DNA from a template strand

E) Nucleoside triphosphates that serve as the source of the nucleotides A, T, C, and G needed in the synthesis of the new strands of DNA

43) Which statement concerning the biomolecules DNA is incorrect?

A) DNA stands for diribonucleic acid.

B) DNA stores the genetic information of an organism and transmits that information from one generation to another.

C) DNA molecules are located in the nucleus of a cell.

D) Four common bases are found in DNA: adenine, cytosine, guanine, and thymine.

44) DNA is a double-stranded nucleic acid that exists as a double helix. Which is responsible for holding the double helix of DNA together?

A) Phosphodiester bonds between complementary base pairs on each strand

B) β-N-glycosidic linkages between the sugar-phosphate backbone of each strand

C) Disulfide bonds between the cysteine residues on each strand

D) Hydrogen bonding between complementary bases on each strand

45) Hydrogen bonding plays an important role in all but one of the items below. Which one does not involve hydrogen bonding?

A) DNA replication

B) DNA double helix

C) DNA primary structure

D) Synthesis of mRNA from DNA

46) DNA isolated from human cheek cells was found to contain 21% guanine. Which statement concerning the base composition of this DNA sample is true?

A) It contains 79% cytosine.

B) It contains 21% adenine, 21% cytosine, and 21% thymine.

C) It contains 21% cytosine, 29% adenine, and 29% thymine.

D) It is impossible to say anything specific about the percentages of adenine, cytosine, and thymine without further analysis of composition.

47) Which of the following best describes the primary function of mRNA in a cell?

A) To serve as a coenzyme in the enzyme-catalyzed hydrolysis of proteins

B) To serve as the template strand in the synthesis of DNA

C) To transcribe the instructions for protein synthesis from DNA and carry this information to the ribosomes

D) To transport amino acids to the ribosomes for protein synthesis

48) How are the correct amino acids brought to the ribosomes for protein synthesis?

A) By reduced coenzymes that match the codons found on the DNA template strand

B) By the transport protein coenzyme A

C) By tRNA molecules that contain the complementary sequence of an mRNA codon in their anticodon loop

D) Amino acids are synthesized at the ribosomes by the hydrolysis of proteins

49) Which structure correctly represents the dinucleotide sequence GU that is found in RNA?

A)

B)

C)

D)

50) Polynucleotides are named by the sequence of the bases they contain, beginning at the 3' end and using the one-letter abbreviation for the bases.

51) The structure shown is a segment of an RNA strand.

52) DNA consists of two polynucleotide strands that wind into a left-handed double helix.

53) During replication, the two strands of DNA separate and each serves as a template for a new strand. Thus, the original DNA molecule forms two DNA molecules, each of which contains one strand from the parent DNA and one new strand.

54) 3'–TCTCAGAG–5' is the sequence of a newly synthesized DNA segment when the template strand has the sequence 3'–AGAGTCTC–5'.

55) The "cartoon" shown below is an example of an rRNA cloverleaf.

56) In the transcription "cartoon" shown, the direction of transcription is from right to left.

57) The strand of DNA used for RNA synthesis is called the information strand.

58) Transcription forms a messenger RNA molecule with a sequence that is identical to the DNA template strand from which it is prepared.

59) For the DNA segment 3'–ACCTGCCTACCCG–5', the sequence of the mRNA molecule synthesized is 5'–UGGACGGAUGGGC–3'.

60) A chromosome is a segment of a DNA molecule that codes for a specific protein.

61) In the process of translation, the genetic code contained in DNA is rewritten in mRNA, which leaves the nucleus and carries the information to the ribosomes for protein synthesis.

62) Individual mRNAs bring specific amino acids to add to the growing peptide chain.

63) All mutations result in a change in the amino acid sequence coded for by the DNA molecule.

64) The dipeptide produced from the DNA segment CAGCTA is the same as the dipeptide from the DNA segment CAGCTG.

65) The dipeptide produced from the DNA segment CAGCTA is the same as the dipeptide from the DNA segment CAGCTT.

66) When a mutation causes a protein deficiency or results in a defective protein, and the condition is inherited from one generation to another, a genetic disease results.

67) The three key elements needed to form recombinant DNA are: a DNA molecule into which a new DNA segment will be inserted; an enzyme that cleaves DNA at specific locations; and an enzyme from a second organism that will be inserted in the original DNA molecule.

68) Insulin, a hormone used by millions of individuals with diabetes, was the first genetically engineered protein available in significant quantities by recombinant DNA methods.

69) Almost any type of cell—skin, saliva, semen, blood, etc.—can be used to obtain a DNA fingerprint of an individual.

70) A virus is an infectious agent consisting of a DNA molecule and an RNA molecule that is contained within a protein coating.

71) A virus that contains a core of RNA is called a retrovirus.

72) If 22% of the nucleotides in a sample of DNA contain the base adenine (A), then 22% of the nucleotides in the same sample of DNA contain the base guanine (G).

73) If 22% of the nucleotides in a sample of DNA contain the base adenine (A), then 22% of the nucleotides in a sample of DNA contain the base thymine (T).

74) There was a mix-up in the hospital nursery and there is a question as to which baby belongs to a set of new parents. The given gel contains the DNA fingerprint of the new mother (Lane 1), the new father (Lane 2), and two infants (Lanes 3 and 4). The DNA fingerprinting indicated that the infant tested in Lane 4 is the child of these parents.

75) The restriction enzyme BamHI recognizes the DNA sequence GGATCC and cuts the DNA between the two G's. Given the segment of double-stranded DNA shown below

the sticky ends that result from cleavage with this enzyme are

76) If a single strand of a gene contains 726 bases, 242 amino acids will make up the polypeptide prepared from it, assuming every base of the gene is transcribed and then translated.

77) Cidofovir (structure shown) is an antiviral medication for the treatment of cytomegalovirus (CMV) retinitis in patients with AIDS that suppresses CMV replication by selective inhibition of viral DNA synthesis. Cidofovir contains the nucleoside cytidine.

78) When inserted into a bacterium, recombinant DNA can be used to prepare large quantities of useful proteins.

79) A triplet codon is a sequence of three amino acids in a protein that signals for transcription.

80) The nucleic acid DNA stores the genetic information of a particular organism, while the nucleic acid RNA translates this genetic information into the synthesis of proteins needed by cells for proper function and development.

81) A gene is a portion of a DNA molecule responsible for the synthesis of a single protein.

82) A nucleoside is formed by joining the anomeric carbon of the monosaccharide with a nitrogen atom of the base.

83) Nucleosides are formed by adding a phosphate group to the 5'-OH of a nucleotide.

84) When the base guanine is added to the 2'-OH of the monosaccharide ribose, the product is guanosine.

85) Nucleic acids are formed by joining the 3'-OH group of one nucleotide with the 5'-phosphate of a second nucleotide in a phosphodiester linkage.

86) The primary structure of a polynucleotide is the sequence of nucleotides that it contains, which is determined by the identity of the bases.

87) The double-stranded DNA helices wind around a core of protein molecules called ________ to form a chain of ________.

88) The synthesis of messenger RNA from DNA is called ________.

89) In DNA replication, the ________ strand grows continuously, while the lagging strand is synthesized in small fragments.

90) The point at which unwinding occurs in DNA is called the ________.

91) A ________ is a complex of a single DNA molecule and proteins wrapped tightly together in a bundle.

92) The sequence of three nucleotides (a triplet) that codes for a specific amino acid is called a/an ________.

93) Each individual tRNA contains a/an ________ of three nucleotides that is complementary to the codon in mRNA and identifies an individual amino acid.

94) A/An ________ mutation is the substitution of one nucleotide for another.

95) A/An ________ mutation occurs when one or more nucleotides is added to a DNA molecule.

96) ________ is synthetic DNA that contains segments from more than one source.

97) In the ________ a portion of a DNA molecule is amplified, producing millions of copies of a single molecule.

98) ________ is an mRNA sequence that codes for the dipeptide Cys–Trp.

99) There was a mix-up in the hospital nursery and there is a question as to which baby belongs to a set of new parents. The given gel contains the DNA fingerprint of the new mother (Lane 1), the new father (Lane 2), and two infants (Lanes 3 and 4). The DNA fingerprinting indicates that the infant tested in Lane ________ is the child of these parents.

100) The mRNA codon CAU specifies the amino acid histidine (His). The anticodon loop of the tRNA molecule that carries His to the ribosomes contains the sequence ________.