molecular genetics exam one
b
A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This DNA molecule could be comprised of a. 120 adenine and 120 uracil molecules. b. 120 thymine and 120 adenine molecules. c. 120 cytosine and 120 thymine molecules. d. 240 adenine and 240 cytosine molecules. e. 240 guanine and 240 thymine molecules.
b
A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This DNA molecule could be comprised of a. 120 adenines and 120 uracils. d. 240 adenines and 240 cytosines. b. 120 thymines and 120 adenines. e. 240 guanines and 240 cytosines. c. 120 cytosines and 120 thymines.
e
A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This DNA molecule could be comprised of a. 120 adenines and 120 uracils. d. 240 guanines and 240 cytosines. b. 120 cytosines and 120 adenines. e. none of the above c. 120 thymines and 120 guanines.
c
A double-stranded DNA molecule contains a total of 120 purines and 120 pyrimidines. This DNA molecule could be comprised of a. 120 adenines and 120 uracils. d. 240 guanines and 240 cytosines. b. 120 cytosines and 120 adenines. e. none of the above c. 120 cytosines and 120 guanines.
a
A gene with 3 introns could (under "normal" circumstances) produce a maximum of __ different MRNAS by alternative splicing. a. 4 b. 5 c. 6 d. 7 e. 8
c
A geneticist introduces a transgene has integrated into the yeast genome. In four of the into yeast cells and isolates five independent cell lines in which the transgene lines, the transgene is expressed strongly, but in the fifth there is no expression at all. A likely explanation for the lack of transgene expression in the fifth cell line is that the a. transgene integrated into a region of the genome characterized by high histone acetylation. b. transgene integrated into a cuchromatic region of the genome. c. transgene integrated into a heterochromatic region of the genome d. host cell lacks the enzymes necessary to express the transgene. e. transgene was mutated during the process of integration into the host cell genome
e
A new DNA strand elongates only in the 5' to 3' direction because a. DNA polymerase begins adding nucleotides at the 5' end of the template. b. RNA primers prevent elongation in the 3' to 5' direction. c. the polarity of the DNA molecule prevents addition of nucleotides at the 3' end d. replication must progress toward the replication fork. e. DNA polymerase can only add nucleotides to the free 3' end.
e
A new DNA strand elongates only in the 5' to 3' direction because a. DNA polymerase begins adding nucleotides at the 5' end of the template. b. RNA primers prevent elongation in the 3' to 5' direction. c. the polarity of the DNA molecule prevents addition of nucleotides at the 3' end. d. replication must progress toward the replication fork. e. DNA polymerases can only add nucleotides to the free 3' end.
d
A single base substitution of a G with an A in the 3rd position of a UGG codon is called a and will result in a mutation if it occurs within a coding region. a. transition/missense d. transition/nonsense b. transversion/missense e. transversion/nonsense c. transition/missense or silent
a
A single base substitution of a U with an A in the 2nd position of a UUA codon is called a __ and will result in a __ mutation if it occurs within a coding region. a. transversion/nonsense b. transition/missmse c. transvenion/missense d. transition/missense or silent d. transition/nonsense f. tranversion/frameshift g. transversion/silent
b
A space probe returns with a culture of a carbon-based life-form that has DNA. You grow microorganism found on a distant planet. Analysis shows that it is a the cells in 15N medium for several generations and then transfer them to 14N medium for two generation. Which pattern in the figure above would you expect if the DNA was replicated in a conservative manner? a. A b. В с. С d. D е. Е
e
A space probe returns with a culture of a carbon-based life-form that has DNA. You grow the cells in 15N medium for several microorganism found on a distant planet. Analysis shows that it is a generations and then transfer them to 14N medium for two generation. Which pattern in the figure above would you expect if the DNA was replicated in a dispersive manner? a. B b. C с. D d. E е. None of the above
d
After mixing a heat-killed, fluorescent strain of bacteria with a live non fluorescent strain you discover that some of the living cells are now fluorescent. The best evidence that the ability to fluoresce is a heritable trait would be an observation that a. fluorescent molecules passed from the heat-killed strain to the living strain. b. protein passed from the heat-killed strain to the living strain. c. DNA passed from the heat-killed strain to the living strain. d. descendants of the living fluorescent cells are also fluorescent e. all of the above
a
After mixing a heat-killed, phosphorescent strain of bacteria with a living non-phosphorescent strain, you discover that some of the living cells are now phosphorescent. The best evidence that the ability to fluoresce is a heritable trait would be an observation that b. protein passed from the heat-killed strain to the living strain a. descendants of the living phosphorescent cells are also phosphorescent. c. the phosphorescence in the living strain is especially bright. d. DNA passed from the heat-killed strain to the living strain. e. both DNA and protein passed from the heat-killed strain to the living strain.
a
After mixing a heat-killed, tetracycline (tet) resistant strain of bacteria with a live susceptible strain you discover that some of the living cells are now tet resistant. The best evidence that the ability to survive in the presence of tetracycline is a heritable trait would be an observation that a. descendants of the living tet resistant cells are also tet resistant. b. tetracycline inhibitor passed from the heat-killed strain to the living strain. c. DNA passed from the heat-killed strain to the living strain. d. proteins passed from the heat-killed strain to the living strain. e. RNA passed from the heat-killed strain to the living strain.
c
After mixing a heat-killed, tetracycline resistant strain of bacteria with a living tetracycline (tet) sensitive strain, you discover that some of the living cells are now tetracycline resistant. The best evidence that the ability to survive in the presence of tetracycline is a heritable trait would be an observation that a. tetracycline degradation enzyme passed from the heat-killed strain to the living strain. b. protein passed from the heat-killed strain to the living strain. c. descendants of the living tet resistant cells are also tet resistant. d. DNA passed from the heat-killed strain to the living strain. e. all of the above except b.
e
Altering which of the following levels of structural organization could change the function of a protein? a. primary c. tertiary e. all of the above b. secondary d. quaternary
c
An extraterrestrial life form is discovered. It has a genetic code much like that of organisms on Earth except that there are five different DNA bases instead of four and the base sequences are translated as doublets instead of triplets. What is the maximum number of different amino acids that could be accommodated by this genetic code assuming that one codon has to specify termination of translation (stop codon)? a. 10 b. 11 c. 24 d. 25 e. 36
a
An extraterrestrial life form is discovered. It has a genetic code much like that of organisms on Earth except that there are five different DNA bases instead of four and the base sequences are translated as doublets instead of triplets. What is the maximum number of different amino acids that could be accommodated by this genetic code assuming that two codons specify termination of translation (stop codons)? a. 23 b. 10 c. 14 d. 15 e. 24 f. 25
c
An extraterrestrial life form is discovered. It has a genetic code much like that of organisms on Earth except that there are five different DNA bases instead of four and the base sequences are translated as doublets instead of triplets. What is the maximum number of different amino acids that could be accommodated by this genetic code assuming that two codons specify termination of translation (stop codons)? a. 8 b. 10 с. 23 d. 24 e. 25
c
An extraterrestrial life form is discovered. It has a genetic code much like that of organisms on Earth except that there are five different DNA bases instead of four and the base sequences are translated as doublets instead of triplets. What is the maximum number of different amino acids that could be accommodated by this genetic code assuming that two codons specify termination of translation (stop codons)? а. 8 b. 10 с. 23 d. 24 e. 25
d
Assume that the following single strand of DNA was synthesized using standard dATP, dGTP, dCTP, and dTTP precursors; however, the innermost phosphate (alpha P) of all the dATPs was labeled with 32P. 3'-CTAGTAT-5 Assume also that the strand was degraded to completion by the enzyme spleen diesterase. Spleen diesterase cleaves DNA at the covalent bond that connects the 5' carbon of the sugar to the phosphate. Which of the resulting nucleotide(s) might now carry the 32P? a. A, C and G c. A and C e. A, C, G and T b. A only d. G and T
d
Assume that the following single strand of DNA was synthesized using standard dATP, dGTP, dCTP, and dTTP precursors; however, the innermost phosphate (alpha P) of all the dATPs was labeled with 32P. 3'-СТАGTAТ-5' Assume also that the strand was degraded to completion by the enzyme spleen diesterase. Spleen diesterase cleaves DNA at the covalent bond that connects the 5' carbon of the sugar to the phosphate. Which of the resulting nucleotide(s) might now carry the 32P? a. A, C and G c. A and C e. A, C, G and T b. A only d. G and T
a
At which level of protein structure are peptide bonds most important? a. primary c. tertiary e. globular b. secondary d. quaternary
b
Cytosine makes up 20% of the nucleotides in a sample of DNA from a cellular organism. Approximately, what percentage of the nucleotides in this sample will be thymine? a. 20 c. 40 e. Impossible to predict b. 30 d. 60
b
Cytosine makes up 20% of the nucleotides in a sample of DNA from a cellular organism. Approximately, what percentage of the nucleotides in this sample will be thymine? а. 20 c. 40 e. can't predict b. 30 d. 60
d
Cytosine makes up 30% of the nucleotides in a sample of DNA from a cellular organism. Approximately, what percentage of the nucleotides in this sample will be adenine? a. 50 c. 30 e. Impossible to predict b. 40 d. 20
a
Cytosine makes up 30% of the nucleotides in a sample of DNA from a cellular organism. Approximately, what percentage of the nucleotides in this sample will be guanine and adenine? a. 50 b. 40 c. 30 d. 20 e. 60 f. can't predict
b
Cytosine makes up 30% of the nucleotides in a sample of DNA from a cellular organism. Approximately, what percentage of the nucleotides in this sample will be guanine and adenine? а. 60 с. 40 e. Impossible to predict b. 50 d. 30
a
Cytosine makes up 30% of the nucleotides in a sample of DNA from a celuar organism. Approximately what percentage of the nucleotides in this sample will be guanine and adenine a. 50 b. 60 c. 30 d. 20 e. 60 f. cant predict
d
DNA Polymerases preferentially use DNTPS instead of NTPS a. because NTPS are present in very small amounts, much lower than dNTPs b. because NTPS cannot enter the active site c. NTPS are used but immediately removed by the proofreading activity DNA Pol. d. because ribose has an extra oxygen which makes it difficult to place the alpha P in the right position for the catalysis e. because ribose has one less oxygen which makes it difficult to place the alpha P in the right position for the catalysis
d
DNA Polymerases preferentially use dNTPs instead of NTPS a. because NTPS are present in very small amounts, much lower than dNTPs b. because NTPS cannot enter the active site c. NTPS are used but immediately removed by the proofreading activity DNA Pol. d. because ribose has an extra oxygen which makes it difficult to place the alpha P in the right position for catalysis e. because ribose has one less oxygen which makes it difficult to place the alpha P in the right position for the catalysis
d
DNA polymerase moves along the template strand of DNA in the __ direction, and adds nucleotides to the __ end of the newly synthesized strand. a. 3' to 5'; 5' d. 3' to 5'; 3' b. 5' to 3'; 3' e. b. or d. depending on the polymerase c. 5' to 3'; 5'
c
DNA polymerase moves along the template strand of DNA in the __ direction, and adds nucleotides to the __ end of the newly synthesized strand. a. 5' to 3'; 5" d. 3' to 5'; 5' b. 5' to 3'; 3' e. b. or d. depending on the polymerase c. 3' to 5'; 3'
c
Each of the following is a modification of the sentence THECATATETHERAT A.THERATATETHECAT B.THECTTATETHERAT C.THECATATEHERAT D.THECATATETHERA E.CATATETHERAT Which of the above is analogous to a frameshift mutation? а. А b. В с. С d. D е. Е
b
Each of the following is a modification of the sentence THECATATETHERAT A.THERATATETHECAT B.THECTTATETHERAT C.THECATATEHERAT D.THECATATETHERA E.CATATETHERAT Which of the above is analogous to a single bp substitution mutation? a. A b. В c. C d. D e. E
b, c
Each of the following is a modification of the sentence THECATATETHERAT. A THERATATETHECAT B. THECTTATETHERAT C THECATATETHECAT D. THECATATETHERA E CATATETHERAT Which of the above is analogous to a single bp substitution mutation? Pick ALL that apply.
c
Each of the following is a modification of the sentence THECATATETHERAT. A THERATATETHECAT B. THECTTATETHERAT C. THECATATEHERAT D. THECATATETHERA E CATATETHERAT Which of the above is analogous to a frameshift mutation?
d
Each of the following is a modification of the sentence THECATATETHERAT. A. THERATATETHECAT B. THETACATETHERAT C. THECATARETHERAT D. THECATATTHERAT E. CATATETHERAT Which of the above is analogous to a frameshift mutation? a. A b. В с. С d. D е. Е
c
Each of the following is a modification of the sentence THECATATETHERAT. A. THERATATETHECAT B. THETACATETHERAT C. THECATARETHERAT D. THECATATTHERAT E. CATATETHERAT Which of the above is analogous to a single bp substitution mutation? а. А b. В c. C d. D е. Е
d
Each of the following is a modification of the sentence THECATATETHERAT. A. THERATATETHECAT B. THETACATETHERAT C. THECATARETHERAT D. THECATATTHERATE E. CATATETHERATRAT Which of the above is analogous to a frameshift mutation? а. А b. В с. С d. D e. E
c
Each of the following is a modification of the sentence THECATATETHERAT. A. THERATATETHECAT B. THETACATETHERAT C. THECATARETHERAT D. THECATATTHERATE E. CATATETHERATRAT Which of the above is analogous to a single bp substitution mutation? a. A b. В с. С d. D е. Е
d
Each of the following is a modification of the sentence THECATATETHERAT. A.THERATATETHECAT B.THEATETHERAT C.THECATACETHERAT D.THCATATETHERAT E.THECATATETHERA Which of the above is analogous to a frameshift mutation? a. A b. В с. С d. D е. Е
c
Each of the following is a modification of the sentence THECATATETHERAT. A.THERATATETHECAT B.THEATETHERAT C.THECATACETHERAT D.THCATATETHERAT E.THECATATETHERA Which of the above is analogous to a single bp substitution mutation? a. A b. В c. C d. D e. E
d
Figure 2. Here is a sketch of a replication bubble, as vou might see in E. coli, Arrows inside the bubble indicate the direction of the replication forks. If the arrow outside the bubble represents the 3' end of the strand it is nearest, where is(are) the most likely place(s) to see the Okazaki fragments? a. positions closest to letters (f) and (g) d. position closest to letters (c) and (a) b. positions closest to letters (c) and (e) e. positions closest to letters (d) and (e) c. position closest to letter (d) only
b
Genomics includes the study of all of the following except a. identifying the location of all of the genes present in the genome. b. studying how the genome is duplicated and segregated within the cell cycle. c. studying the coordinated expression of groups of genes under various conditions or in different cell types. d. comparing genomes between different organisms. e. identifying the functions of all of the genes in the genome.
d
Helix-turn-helix motif can be described as a. a tertiary structure of a protein b. an A or B form of nucleic acid c. a secodary structure of DNA d. a super secondary structure of a protein e. a supersecondary structure of RNA f. a quaternary structure of a protein
b
Here is a diagram of DNA replication in E.coli. The darker strands are newly synthesized, #1 points to the new strand in the top duplex and #4 in the bottom duplex. Use this diagram to answer several questions below. Refer to figure above. DNA Pol III is indicated by # __ and its proofreading activity is accomplished by __. a. 2/5' to 3' exonuclease d. 5/ATP hydrolysis b. 2/3' to 5' exonuclease e. 5/endonuclease cleavage c. 2/reverse reaction by polymerase
d
Here is a diagram of DNA replication in E.coli. The darker strands are newly synthesized, #1 points to the new strand in the top duplex and #4 in the bottom duplex. Use this diagram to answer several questions below. Refer to figure above. The enzyme/protein labeled #6 is a a. DNA Pol III d. topoisomerase b. helicase e. none of the above c. primase
c
Here is a diagram of DNA replication in E.coli. The darker strands are newly synthesized, #1 points to the new strand in the top duplex and #4 in the bottom duplex. Use this diagram to answer several questions below. Refer to figure above. The helicase is indicated by # __ and in E.coli it "moves" in __ direction. a. 2/5' to 3' d. 5/3' to 5' b. 2/3' to 5' e. c. and d. only c. 5/5' to 3'
e
Here is a sketch of a replication bubble, as you might see in E. coli. Arrows inside the bubble indicate the direction of the replication forks. If arrow outside the bubble represents the 5' end of the strand it is nearest, where is (are) the most likely place(s) to see the Okazaki fragments? a. positions closest to letters (f) and (g) d. position closest to letters (c) and (a) b. positions closest to letters (c) and (e) e. positions closest to letters (d) and (e) c. position closest to letter (d) and (a)
e
Hershey/Chase experiments (using T2 bacteriophages labeled with radioactive sulfur and radioactive phosphorus) demonstrated all of the following except: a. most of the radioactive phosphorus entered the cells. b. DNA is the genetic material of T2 phages. c. DNA was injected into bacteria. d. most of the proteins remained on the outer surface of bacteria. e. most of the radioactive sulfur entered bacterial cells.
b
Hershey/Chase experiments (using T2 bacteriophages labeled with radioactive sulfur and radioactive phosphorus) demonstrated all of the following except: a. most of the radioactive phosphorus entered the cells. b. RNA is the genetic material of T2 phages. c. DNA was injected into bacteria. d. most of the proteins remained on the outer surface of bacteria. e. most of the radioactive sulfur remained on the outer surface of bacteria.
e
How does DNA polymerase discriminate between the insertion of correct and incorrect base pairs as DNA replication proceeds? a. Incorrect nucleotides repel each other because of their charges. b. Correct base paring of template and the incoming DNTP allows for proper positioning of the substrates within the active site. c. If the new "base pair" exhibits improper geometry within the active site the incorrect nucleotide will not be incorporated and will diffuse away. d. All of the above e. b. and c. only
e
How does DNA polymerase discriminate between the insertion of correct and incorrect base pairs as DNA replication proceeds? a. Incorrect nucleotides repel each other because of their charges. b. Correct base paring of template and the incoming dNTP allows for proper positioning of the substrates within the active site. с. If the new "base pair" exhibits improper geometry within the active site the incorrect nucleotide will not be incorporated and will diffuse away. d. All of the above e. b. and c. only
d
Hydrogen bonding would be possible between which two amino acids in the figure above? a. 1 and 3 b. 2 and 6 c. 3 and 6 d. 1 and 5 e. 3 and 5
c
Hydrophobic interactions would occur between which two amino acids in the figure above? a. 1 and 4 b. 2 and 5 c. 3 and 6 d. 2 and 4 e. 3 and 5
b
If there are 5 restriction sites (recognition sequences) for a restriction enzyme A in a DNA molecule and the digestion yields 5 fragments a. the molecule was linear b. the molecule was circular (had no free ends) c. the molecule was either linear or circular d. the molecule was linear and single stranded e. none of the above is true
d
In an analysis of the nucleotide composition of DNA, which of the following is true? a. A = C c. A+T= G+C e. both c. and d. b. A= G and C =T d. G+A = T+C
c
In an analysis of the nucleotide composition of any double stranded DNA, which of the following is true? a. A=G and C =T c. G+T= A+C e. b. and d. only b. A+T=G +C d. A+T/G+C = 1
a
In an analysis of the nucleotide composition of any double stranded DNA, which of the following is true? a. G+T= A+ C b. A = G and C =T c. A+T= G+ C d. A+T/G+C = 1 e. A=C and G=T
e
In an analysis of the nucleotide composition of double stranded DNA, which of the following is true? a. A=G c. A+T= G+C e. b. and d. only b. A = T and C = G d. G+A = T+C
e
In trying to determine whether DNA or protein is the genetic material of T2 phages, Hershey and Chase made use of which of the following facts? a. DNA does not contain sulfur, whereas protein does. b. DNA contains phosphorus, but protein does not. c. DNA contains nitrogen, whereas protein does not. d. all of the above e. a. and b. only
c
In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts? a. DNA contains sulfur, whereas proteins do not. b. DNA contains nitrogen, whereas proteins do not. c. Proteins contain sulfur, whereas DNA does not. d. all of the above e. b and c. only
d
In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts? a. DNA does not contain sulfur, whereas protein does. b. DNA contains phosphorus, but protein does not. c. DNA contains nitrogen, whereas protein does not. d. a. and b.only e. all of the above
a, e
In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts? Select all correct answers. a. DNA contains phosphorus, whereas proteins do not. b. DNA contains sulfur, whereas proteins do not. c. Both proteins and DNA contain sulfur and nitrogen. d. Both proteins and DNA contain carbon e. Proteins contain sulfur, whereas DNA does not. f. Proteins contain nitrogen whereas DNA does not.
a
RFLP analysis can be used to distinguish between alleles based on differences in a. restriction enzyme recognition sites between the alleles. b. the amount of DNA amplified from the alleles during PCR. c. the ability of the alleles to be replicated in bacterial cells. d. the proteins expressed from the alleles. e. the ability of nucleic acid probes to preferentially hybridize to the alleles.
b
RNA primers are used in DNA replication because a. primase does not require a template. b. DNA polymerases require primers but RNA polymerases do not. c. DNA polymerase can initiate DNA synthesis but with NTPS only. d. all of the above e. a. and b. only
c
RNA primers are used in DNA replication because a. primase does not require a template. b. they allow for elongation in the 3' to 5' direction (addition of nucleotides to 5' end). c. DNA polymerase cannot initiate DNA synthesis without a primer. d. all of the above. e. only a. and c
c
RNA primers are used in DNA replication because a. primase does not require a template. b. they allow for elongation in the 3' to 5' direction (addition of nucleotides to 5' end). c. DNA polymerase cannot initiate DNA synthesis without a primer. d. all of the above. e. only a. and c.
c
Refer to Figure 1. The use of antibiotic medium at the end of this process: a. selects against plasmids containing human DNA fragments. b. selects for plasmids containing particular DNA fragments. c. selects for bacteria containing plasmids. d. selects for bacteria lacking plasmids. e. prevents contamination of the medium.
b
Refer to Figure 1. What process or enzyme was used for Step 3 in the accompanying figure? a. sequencing b. transformation c. transduction d. a DNA ligase e. a restriction enzyme
b
Refer to Figure 5. The molecular fragment represented in the accompanying figure is: a. ATP. c. a protein. e. DNA. b. RNA. d. a nucleotide.
d
Refer to Figure 5. The type of connection between the atoms at the point labeled 1 is a. a peptide bond. d. a phosphodiester linkage. b. a glycoside linkage. e. a hydrogen bond. c. a disulfide bond.
b
Refer to fig. above. The correct designation for the structure or position labeled C is: a. the leading strand. d. polymerase. b. 5' end. e. 3' end. c. Okazaki fragment.
b
Refer to fig. above. The white portions only of structures represented by the letter F are: a. composed entirely of DNA. d. identical primers. b. composed entirely of RNA е. both b. and d. c. called Okazaki fragments.
b
Refer to figure above. The correct designation for the structure or position labeled A could be: a. the leading strand template. d. the lagging strand. b. 5' end. e. b. or d. only c. Okazaki fragment.
b
Refer to figure above. The structures represented by the letter E (white and black portions) are: a. composed entirely of DNA. d. composed of RNA only b. composed of RNA and DNA e. b. and d. only c. called primers
a
Refer to the narrative above to answer this question. 2. Bacteria that contain the nonrecombinant (empty plasmid with no insert) plasmid would grow În a. all four types of broth. b. in the nutrient broth without antibiotics only. c. only in the broth containing both antiblotics. d. In the broth containing tetracycline, but not In the broth containing ampicilin. e. in the nutrient broth plus ampicillin, but not in the broth containing tetracycline.
e
Restriction mapping establishes: a. a protocol by which genes can be located. b. the sequences of nucleotides in a DNA sequence. c. a starting point for transcription of mRNA. d. the information gained by the use of radioactive DNA probes. e. landmarks in a cloned DNA fragment.
a
Ribose differs from deoxyribose by having: a. an extra oxygen. b. one less oxygen. c. one less hydrogen. d. an extra carbon in the ring. e. an extra hydrogen.
a
Ribose differs from deoxyribose by having: a. an extra oxygen. d. an extra carbon in the ring. b. one less oxygen. e. an extra hydrogen. c. one less hydrogen.
b
Ribose differs from deoxyribose by having: a. one less oxygen. d. an extra carbon in the ring. b. an extra oxygen. e. an extra hydrogen. c. one less hydrogen.
d
Statement A. Genetic information in viruses and other "gene creatures" is always in the form of single or double stranded DNA Statement B. Genetic information in cellular organisms may be in a form of double stranded DNA or RNA. a. only A is true с. c. both A and B are true b. only B is true d. both A and B are false
b
Statement A. Genetic information in viruses and other gene "creatures" may be in the form of RNA or DNA. Statement B. Genetic information in cellular organisms may be in the form of a double stranded DNA or RNA. a. both A and B are false b. only A is true c. both A and B are true d. only B is true
c
Statement A. Genetic information in viruses and other gene "creatures" may be only in the form of DNA or RNA. Statement B. Genetic information in cellular organisms may be in the form of a double stranded DNA only. a. only A is true c. both A and B are true b. only B is true d. both A and B are false
c
Statement A. Genetic information in viruses can be provided by either DNA or RNA Statement B. Genetic information in cellular organisms is always in the form of double stranded DNA a. only A is true c. both A and B are true b. only B is true d. both A and B are false
d
Statement A. Prokaryotic cells can acquire a new phenotype as a result of transformation by added protein. Statement B. Eukaryotic cells can acquire a new phenotype as a result of transfection by added RNA. a. only A is true b. only B is true c. both A and B are true d. both A and B are false
a
Statement A. The positions, lengths and sequences of exons are usually well conserved when homologous (related) genes are compared between different organisms, but the lengths and sequences of the introns may vary greatly. Statement B. Exons evolve much more rapidly than introns because of the lack of selective pressure since they do not code for proteins. a. only A is true b. only B is true c. both A and B are true d. both A and B are false
e
Substitution of C with A is called a __ and will result in a __ mutation if it occurs in the 3rd position of an UGC codon. a. transversion/frameshift c. transversion/missense e. transversion/nonsense b. transition/nonsense d. transition/missense
b
Substitution of G with A is called a __ and will result in a __ mutation if it occurs in the 2nd position of a UGG codon a. transition/frameshift c. transversion/missense e. transversion/nonsense b. transition/nonsense d. transition/missense
a
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 c. chromosomal e. None of the above b. frameshift d. missense
a
The DNA double helix has a uniform diameter because __ which have two rings, always pair with __ which have one ring. a. purines; pyrimidines b. ribose sugars; deoxyribose sugars c. nucleotides; nucleoside d. triphosphates pyrimidines; purines e. deoxyribose sugars; ribose sugars f. nucleotide diphoshates; nucleotide monophoshates
a
The DNA double helix has a uniform diameter because __ which have two rings, always pair with__ which have one ring. a. purines; pyrimidines d. ribose sugars; deoxyribose sugars b. pyrimidines; purines e. nucleotides; nucleoside triphosphates c. deoxyribose sugars; ribose sugars
c
The DNA strand growing away from the replication fork grows __ in a 5'->3' direction as the replication fork advances and is called the__. a. discontinuously, leading strand d. continuously, leading strand b. continuously, lagging strand e. semicontinously, lagging strand c. discontinuously, lagging strand
c
The R group or side chain of the amino acid glycine is --H. The R group or side chain of the amino acid alanine is -CH3. Where would you expect to find these amino acids in a globular protein in aqueous solution a. Glycine would be in the interior, and alanine would be on the exterior of the globular protein. b. Alanine would be in the interior, and glycine would be on the exterior of the globular protein. c. Both glycine and alanine would be in the interior of the globular protein. d. Both glycine and alanine would be on the exterior of the globular protein. e. Both glycine and alanine would be in the interior and on the exterior of the globular protein.
c
The R group or side chain of the amino acid methionine is -CH,-CH,-S-CH3. The R group or side chain of the amino acid alanine is -CH. Where would you expect to find these amino acids in a globular protein in aqueous solution? a. Methionine would be in the interior, and alanine would be on the exterior of the globular protein. b. Alanine would be in the interior, and methionine would be on the exterior of the globular protein. c. Both methionine and alanine would be in the interior of the globular protein. d. Both methionine and alanine would be on the exterior of the globular protein. e. both b. and c. are equally likely
b
The R group or side chain of the amino acid methionine is -CH2-CH2-S-CH, The R group or side chain of the amino acid alanine is - CH3. Where would you expect to find these amino acids in a globular protein in an aqueous solution? a. Both methionine and alanine would be on the exterior of a globular protein. b. Both methionine and alanine would be in the interior of a globular protein. c. Impossible to predict because both Alanine and Methionine couls be found elther on the exterior or the interior, Alanine would be in the interior, and methlonine would be on the exterior of a globular proteln. d. Methionine would be in the interlor, and alanine would be on the exterior of a globular protein.
c
The R group or side chain of the amino acid serine is -CH2OH. The R group or side chain of the amino acid alanine is -CH3. Where would you expect to find these amino acids in a globular protein in an aqueous solution? a. Serine would be in the interior, and alanine would be on the exterior of the globular protein. b. Both serine and alanine would be on the exterior of the globular protein. с. Alanine would be in the interior, and serine would be on the exterior of the globular protein d. Both serine and alanine would be in the interior of the globular protein. e. All of the above are equally likely.
d
The chemical reaction illustrated in the figure below results in the formation of a (an) a. ionic bond. d. peptide bond. b. hydrogen bond e. phosphodiester linkage. c. glycosidic linkage.
b
The coding strand of DNA is also called a. antisense c. template e. both b. and c. b. sense d. CDNA
b
The coding strand of DNA is also called a. antisense с. template e. both b. and d. b. sense d. CDNA
a, e
The coding strand of DNA is also called Pick all that apply a. sense b. anitsense c. template d. noncoding e. nontemplate f. CDNA
d, e, f
The condensation reaction (also called dehydration synthesis) involving 2 amino acids results in __. Select ALL that apply. a. a formation of disaccharide b. a formation of lonic bond c. a formation of a hydrogen bond d. a formation of water molecule e. a formation of peptide bond f. a formation of a dipeptide g. a formation of phoshodiester linkage h. a formation of a polypeptide
e
The enzyme polynucleotide phosphorylase randomly assembles nucleotides into a polynucleotide polymer. You add p. phosphorylase to a solution of adenosine triphosphate, cytosine triphosphate and guanosine triphosphate. The resulting artificial mRNA molecule would have__possible different codons if the code involved two-base sequences and__possible different codons if the code involved three-base sequences. a. 2; 3 b. 2; 4 c. 4; 8 d. 8; 16 e. 9; 27
d
The fidelity of DNA replication can be traced to which of the following activities? a. accurate selection of nucleotides d. a and b only b. immediate proofreading e. a, b and c c. postreplicative recombination
e
The fidelity of DNA replication in E. coli can be traced to which of the following activities? a. accurate selection of nucleotides d. all of the above b. proofreading by 3' to 5' exonuclease e. a. and b. only c. reverse reaction by Polymerase
b
The figure below best illustrates a. a quaternary structure of a protein b. a beta barrel motif of a protein c. a type of super secondary structure of a polynucleotide d. all of the above. e. b. and c. only.
e
The figure below best illustrates b. a double helix of a nucleic acid e. c. and d. only. a. a primary structure of a peptide. d. a secondary structure of a peptide с. an alpha helix of a peptide.
c
The figure below best illustrates the a. double helix of RNA d. double helix of DNA. b. tertiary structure of a polypeptide. e. a. or d. only. c. secondary structure of a polypeptide.
a
The figure below best illustrates the a. secondary structure of a polypeptide. d. double helix structure of DNA. b. tertiary structure of a polypeptide. e. primary structure of a polysaccharide. c. quaternary structure of a protein.
c
The genetic code is essentially the same for all organisms. From this, one can logically assume all of the following except a. a gene from an organism could theoretically be expressed by any other organism. b. all organisms have a common ancestor. c. DNA was the first genetic material. d. the same codons in different organisms usually translate into the same amino acids. e. different organisms have the same number of different types of amino acids.
e
The molecular fragment represented in the accompanying figure is: а. АТР. c. a peptide. e. none of the above. b. DNA d. a nucleotide.
d
The molecule above (entire fragment) most likely is a. an oligopeptide c. helical e. a nucleotide b. DNA d. water soluble
e
The molecules (or "groups") that form the backbone of a polynucleotide chain are: a. the four bases. c. bases and phosphates. e. none of the above b. bases and sugars. d. sugars only
e
The molecules (or "groups") that form the backbone of a polynucleotide chain are: a. the four bases. c. bases and phosphates. e. none of the above b. bases and sugars. d. sugars only.
e
The noncoding strand of DNA is also called a. antisense c. template e. both a. and c. b. sense d. CDNA
c
The noncoding strand of DNA is also called a. nonsense d. top strand b. sense e. both b. and c. are correct c. template
a
The primary structure of proteins is maintained (held) by a. peptide bonds b. phoshodiester bonds c. hygrogen bonds d. ionic bonds e. hydrophobic interactions
d
The questions refer to interactions between R groups Ionic bonds would be possible between which two amino acids in the figure above? a. I and 5 b. 2 and 6 c. 4 and 5 d. 2 and 4 e. 2 and 5
c
The questions refer to interactions between R groups. Hydrogen bonding would be possible between which two amino acids in the figure above? a. 1 and 6 b. 2 and 3 c. 2 and 5 d. 1 and 3 e. 2 and 6
b
The segment of DNA shown in the figure below has restriction sites I and II, which create restriction fragments A B and C. Which of the gels produced by electrophoresis shown below best represents the separation and identity of these fragments?
c
The two molecules that alternate to form the backbone of a polynucleotide chain are: a. adenine and thymine d. base and sugar. b. cytosine and guanine. e. base and phosphate. c. sugar and phosphate.
e
The type of connection between the atoms at the point labeled "1 " in the accompanying figure is a: a. dipeptide bond. c. disulfide bond. e. phosphodiester linkage. b. diphosphate linkage. d. phospholipid linkage.
e
The type of connection between the sugars (labeled "S") at the point labeled "1 " in the accompanying figure is a: a. peptide bond. c. disulfide bond. e. phosphodiester linkage. b. diphosphate linkage. d. phospholipid linkage.
c
This table gives the results of assays of percentages of bases from genomes obtained from 5 viruses. (Hint: For each virus, determine what type of nucleic acid serves as genetic material and whether it is more likely to be single or double stranded.) Refer to Table 1. Which of the statements about the viral genomes is incorrect. a. Although viruses # 2, 3 and 4 all have DNA as their genetic material, these three samples most likely represent different viruses. b. The genome of virus #1 is definitely single-stranded RNA c. The genomes of viruses #2, 4 and 5 are definitely double-stranded d. The genome of virus #5 is made of RNA and it may be double-stranded e. All of the above
c
To avoid the introduction of introns into the vector, a ___ copy of mature mRNA is made, using the enzyme ___. a. rDNA; RNA polymerase d. cRNA; reverse transcriptase b. cDNA; DNA ligase e. rDNA; DNA polymerase c. cDNA; reverse transcriptase
d
Tobacco mosaic virus (TMV) has RNA rather than DNA as its genetic material. In a hypothetical situation where proteins from a TMV were mixed with DNA from a related DNA virus (TMV-related), the result could be a hybrid virus. If that virus were to infect a cell and reproduce, what would the resulting "offspring" viruses be like? a. a hybrid: tobacco mosaic virus protein and nucleic acid from the DNA virus b. tobacco mosaic virus (TMV) c. a hybrid: tobacco mosaic virus RNA and protein from the DNA virus d. the related DNA virus (TMV-related) e. a virus with a double helix made up of one strand of DNA complementary to a strand of RNA surrounded by TMV viral protein
b
Tobacco mosaic virus (TMV) has RNA rather than DNA as its genetic material. Let's say that there is a very similar virus that has DNA as a genetic material and it is called TMV-related. In a hypothetical situation where DNA from a TMV-related virus was mi: with proteins from TMV the result could be a "hybrid" virus. If that hybrid virus were able to infect a cell and reproduce, what would the resulting offspring viruses be like? a. tobacco mosalc viruses (TMV) b. the tobacco mosaic related DNA viruses (TMV-related) c. hybrid viruses: TMV proteins and nucleic acid from the DNA virus (TMV-related) d. viruses with a double helix made up of one strand of DNA and one strand of RNA surrounded by TMV-related viral proteins e. hybrid viruses: tobacco mosalc virus RNA and proteln from the TMV-related virus
b
Tobacco mosaic virus (TMV) has RNA rather than DNA as its genetic material. Let's say that there is a very similar virus that has DNA as a genetic material and it is called TMV-related. In a hypothetical situation where RNA from a tobacco mosaic virus (TMV) was mixed with proteins from TMV-related virus the result could be a "hybrid" virus. If that hybrid virus were able to infect a cell and reproduce, what would the resulting offspring viruses be like? a. hybrid viruses: TMV proteins and nucleic acid from the DNA virus (TMV-related) b. tobacco mosaic viruses (TMV) c. hybrid viruses: tobacco mosaic virus RNA and protein from the TMV-related virus d. the tobacco mosaic related DNA virus (TMV-related) e. viruses with a double helix made up of one strand of DNA and one strand of RNA surrounded by TMV-related viral proteins
e
Two polynucleotide chains must run __ in direction(s) and must be __ if they are to hybridize. a. the same; uncomplementary d. parallel; complementary b. opposite; identical e. antiparallel; complementary c. parallel; uncomplementary
a
Two polynucleotide chains must run in __ direction(s) and must be __ if they are to hybridize. a. antiparalet complementary b. the sme unconplementary c. opposte identical d. parallel complementary e. palel uncomplementary
d
Two polynucleotide chains must run in __ direction(s) and must be __ if they are to hybridize. a. the same; uncomplementary d. antiparallel; complementary b. opposite; identical e. parallel; uncomplementary c. parallel: complementary
b
Use the figure below to answer the following questions. A space probe returns with a culture of a microorganism found on a distant planet. Analysis shows that it is a carbon- based life-form that has DNA. You grow the cells in 15N medium for several generations and then transfer them to 14N medium for one generation. Which pattern in the figure above would you expect if the DNA was replicated in a conservative manner? a. А b. В с. С d. D e. Е
e
Use the figure below to answer the following questions. A space probe returns with a culture of a microorganism found on a distant planet. Analysis shows that it is a carbon- based life-form that has DNA. You grow the cells in 15N medium for several generations and then transfer them to 14N medium for two generations. Which pattern in the figure above would you expect if the DNA was replicated in a dispersive manner? a. В b. C с. D d. E e. none of the above
d
Use the figure below to answer the following questions. A space probe returns with a culture of a microorganism found on a distant planet. Analysis shows that it is a carbon-based life-form that has DNA, You grow the cells in 15N medium for several generations and then transfer them to 14N medium for one generation. Which pattern in the figure above would you expect if the DNA was replicated in a semiconservative manner? а. А b. В с. С d. D e. E
d
Use the figure below to answer the following questions. A space probe returns with a culture of a microorganism found on a distant planet. Analysis shows that it is a carbon-based life-form that has DNA, You grow the cells in 15N medium for several generations and then transfer them to 14N medium for two generations. Which pattern in the figure above would you expect if the DNA was replicated in a semiconservative manner? a. В b. C с. D d. E e. none of the above
b
Use the figure below to answer the following questions. A space probe returns with a culture of a microorganism found on a distant planet. Analysis shows that it is a carbon-based life-form that has DNA. You grow the cells in 15N medium for several generations and then transfer them to 14N medium for one generation. Which pattern in the figure above would you expect if the DNA was replicated in a conservative manner? a. A b. B с. С d. D e. E
e
Use the figure below to answer the following questions. A space probe returns with a culture of a microorganism found on a distant planet. Analysis shows that it is a carbon-based life-form that has DNA. You grow the cells in 15N medium for several generations and then transfer them to 14N medium for two generations. Which pattern in the figure above would you expect to see if the DNA was replicated in a semiconservative manner? a. A b. B с. С d. D e. E
d
Use the figure to answer the following question(s). Hydrogen bonding would be possible between which two amino acid side chains in the accompanying figure (above)? a. 1 and 3 b. 2 and 6 c. 3 and 6 d. 1 and 5 e. 3 and 5
e
Use the figure to answer the following questions. Refer to figure above. The correct designation for the structure or position labeled C is: a. Okazaki fragment c. the leading strand e. template b. 3' end d. polymerase
e
Use the figure to answer the following questions. Refer to figure above. The structures represented by the letter E (both white and black portions) are: a. composed entirely of DNA d. composed of RNA and DNA b. composed entirely of RNA e. both c. and d. c. called Okazaki fragments.
e
Use the figure to answer the following questions. What process or enzyme was used for Step 1 in the figure above? a. exonuclease c. DNA synthesis e. a restriction enzyme b. transformation d. a DNA ligase
b
Use the figure to answer the following questions. What process or enzyme was used for Step 3 in the figure above? a. nuclease c. DNA synthesis e. a restriction enzyme b. transformation d. a DNA ligase
d
Use the figure to answer the following questions. What process or enzyme was used for Step 2 in the figure above? a. exonuclease c. DNA synthesis e. a restriction enzyme b. transformation d. a DNA ligase
a
Use the following information to answer 2 questions below. A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI which is located within the gene for tetracycline resistance. This mixture is incubated for several hours, exposed to DNA ligase, and then used to transform bacteria that are susceptible to both ampicillin and tetracycline. The bacteria are grown on nutrient broth media (without antibiotics) and replica plates are made on 4 types of media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline and nutrient broth with no antibiotics. Bacteria containing a recombinant plasmid into which the eukaryotic gene has integrated would grow in a. the nutrient broth and the ampicillin broth only. b. the nutrient broth and the tetracycline broth only. c. the nutrient broth, the ampicillin broth, and the tetracycline broth. d. all four types of broth. e. the nutrient broth without antibiotics only.
b
Use the following information to answer 2 questions below. A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI which is located within the gene for tetracycline resistance. This mixture is incubated for several hours, exposed to DNA ligase, and then used to transform bacteria that are susceptible to both ampicillin and tetracycline. The bacteria are grown on nutrient broth media (without antibiotics) and replica plates are made on 4 types of media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline and nutrient broth with no antibiotics. Bacteria that contain the nonrecombinant (empty plasmid with no insert) plasmid would grow a. in the nutrient broth without antibiotics only. b. in all four types of broth. c. only in the broth containing both antibiotics. d. in the broth containing tetracycline, but not in the broth containing ampicillin. e. in the nutrient broth plus ampicillin, but not in the broth containing tetracycline.
a
Use the following information to answer questions 1 & 2 EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing recognition site for EcoRI which is located within the gene for tetracycline resistance. This mixture is incubated for several hour exposed to DNA ligase, and then used to transform bacteria that are susceptible to both ampicillin and tetracycline. The bacteri are grown on nutrient broth media (without antibiotics) and replica plates are made on 4 types of media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline and nutrient broth with no antibiotics 1. Bacteria containing a recombinant plasmid into which the eukaryotic gene has integrated would grow in a. the nutrient broth and the ampicillin broth only. b. the nutrient broth without antibiotics only. all four types of broth. c. the nutrient broth and the tetracycline broth only. d. the nutrient broth, the ampicillin broth, and the tetracycline broth. e. nutrient broth containing both antibiotics only
a
Use this for questions 10-12: An eukaryotic DNA fragment has "sticky ends" produced by the restriction endonuclease EcoRI. This DNA is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original cells. Samples of these colonies are then grown in four different media: a. nutrient broth without antibiotics b. nutrient broth plus ampicillin c. nutrient broth plus tetracycline d. nutrient broth plus ampicillin and tetracycline 11. Bacteria that do not take up any plasmids would grow on which media? a. a. only b. a. and b. only c. a. and c. only d. b, c, and d only e. a, b, c, and d
e
Use this for questions 10-12: An eukaryotic DNA fragment has "sticky ends" produced by the restriction endonuclease EcoRI. This DNA is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original cells. Samples of these colonies are then grown in four different media: a. nutrient broth without antibiotics b. nutrient broth plus ampicillin c. nutrient broth plus tetracycline d. nutrient broth plus ampicillin and tetracycline 10. Bacteria that contain empty plasmid without the eukaryotic DNA would grow on a. a. only c. a. and c. only e. a, b, c and d b. a. and b. only d. b, c and d only
b
Use this for questions 10-12: An eukaryotic DNA fragment has "sticky ends" produced by the restriction endonuclease EcoRI. This DNA is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original cells. Samples of these colonies are then grown in four different media: a. nutrient broth without antibiotics b. nutrient broth plus ampicillin c. nutrient broth plus tetracycline d. nutrient broth plus ampicillin and tetracycline 12. Bacteria containing a plasmid with integrated eukaryotic DNA would grow on a. a. only c. a. and c. only e. a, b, c and d b. a. and b. only d. b, c and d only
c
What determines the nucleotide sequence of the newly synthesized strand during DNA replication? a. the particular DNA polymerase catalyzing the reaction b. the relative amounts of the four nucleoside triphosphates in the cell c. the nucleotide sequence of the template strand d. the primase used in the reaction e. both a. and d.
e
What does transformation involve in bacteria? a. the creation of a strand of DNA from an RNA molecule b. the creation of a strand of RNA from a DNA molecule с. the infection of cells by a phage DNA molecule d. the type of semiconservative replication shown by DNA e. assimilation of external DNA into a cell and its incorporation into bacterial chromosome
b
What is a PRION? a. viroid b. Infectious agent composed of ONLY protein c. Infectious microorganism d. an enzyme used for cloning e. Virus
a
Which of the following "tools" of molecular biology is incorrectly paired with its use? a. DNA exonucleases - production of RFLPS b. dideoxyribonucleotides - DNA sequencing c. reverse transcriptase - production of CDNA d. DNA polymerase - DNA sequencing e. None of the above because all pairs are correct
c
Which of the following is FALSE about core histones? a. the all contain an unstructured N-terminal tails b. Many amino acids can be chemically modified which could affect chromatin strudture c. they have several beta strands that are essential to their function d. they are small possitively charged proteins e. they form the octameres of nucleosomes f. they all have 3 alpha helices that form a histone fold motif
a
Which of the following is false a. Prokaryotic DNA is associated with histones and "packaged' in a form of chromatin b. Euchromatin may be transcriptionally active c. Euchromatin is less condensed than heterochromatin d. Heterochromatin is transcriptionally inactive e. None of the above
c
Which of the following is false about A-form double helices? a. they are right- handed with ~ 11 bp/turn b. they are a typical confirmation of some nucleic acids under physiological conditions c. they are never found in nature d. all of the above e. a. and c. only
e
Which of the following is false about complementation test? a. It is used to determine if two mutations with similar phenotypes are in the same gene b. If the progeny of two homozygous (mutant) parents have mutant (not wild type) phenotype the two mutations are in the same complementation group. c. Mutations that complement one another are said to be im different complementation groups d. Another term to describe a complementation group is a gene e. none of the above
e
Which of the following is false about complementation test? a. It is used to determine if two mutations with similar phenotypes are in the same gene b. If the progeny of two homozygous (mutant) parents have mutant (not wild type) phenotype the two mutations are in the same complementation group. c. Mutations that complement one another are said to be in different complementation groups d. Another term to describe a complementation group is a gene e. none of the above
c
Which of the following is false about complementation test? a. It is used to determine if two mutations with similar phenotypes are in the same gene b. If the progeny of two homozygous (mutant) parents have mutant phenotype the two mutations are in the same complementation group. c. Mutations that complement one another are said to be in the same complementation group d. Another term to describe a complementation group is a gene e. none of the above
e
Which of the following is false about gel electrophoresis a. it can be used to fractionate any type of biological macromolecules based on their size alone b. nucleic acids will migrate towards negative electrode (cathode) c. larger fragments of DNA (of higher molecular weight) will migrate though the gel faster than the smaller one: d. a and b only e. a, b and c
b
Which of the following is false about nucleosomes? a. The core is composed of an octamer of 4 different histone proteins b. Each core histone is a small negatively charged protein e. The function of chromatin may be modulated by acetylation, phosphorylation or methylation of core histones d. Each core histone is composed of the histone fold motif and the unstructured amino terminal domain e. None of the above
d
Which of the following is false about the structure labeled "2" in the accompanying figure: a. It is a nitrogenous base. b. It is a purine called guanine. c. It can form 3 hydrogen bonds with cytosine d. It is covalently bonded to 2' carbon of pentose sugar. e. None of the above, because they are all true
b
Which of the following is false about the structure labeled "2" in the accompanying figure: a. It is a nitrogenous base. b. It is a pyrimidine called guanine. с. It can form 3 hydrogen bonds with cytosine d. It is covalently bonded to 1' carbon of pentose sugar. e. None of the above, because they are all true
d
Which of the following is false? a. A deletion of one or two nucleotides within the gene's coding region will usually result in a frameshift mutation b. For most mRNAs only one of the reading frames is OPEN; an ORF с. An insertion of one or two nucleotides within the gene's coding region will usually result in a frameshift mutation d. Blocked reading frames are interrupted by frequent initiation (start) codons e. None of the above
b
Which of the following is false? a. A deletion of one or two nucleotides within the gene's coding region will usually result in a frameshift mutation b. There are always three possible reading frames for any nucleic acid strand no matter what the sequence and composition that will encode three entirely different protein sequences c. For most RNAS only one of the reading frames is OPEN; an ORF d. Blocked reading frames are interrupted by frequent termination (stop) codons e. None of the above
b
Which of the following is false? a. All null mutations are loss-of-function mutations b. A point mutation in a coding region is never silent c. Null allele may result from a deletion of the gene d. Several variants of the same gene are called multiple alleles e. None of the above
b
Which of the following is false? a. All null mutations are loss-of-function mutations b. A point mutation in a coding region is never silent с. c. Null allele may result from a deletion of the gene d. Several variants of the same gene are called multiple alleles e. None of the above
a
Which of the following is false? a. Blocked reading frames are interrupted by frequent Initiation (start) codons b. A deletion o ene or two nucleotides within the gene's coding region will uualy result in a frameshilt mutation c. For most mRNAL only one of the reading trames is OPEN: an ORF d. An insertion of one or two nucleotides within the gene's coding region will usually result in a frameshift mutation e. Adeletion or insertion of 3 consecutive nucieotides within the gene's coding region willi not result in a frameshift mutation
b
Which of the following is false? a. Genes on different chromosomes show independent assortment b. Recombination frequencies (between two loci) of 50% indicate linkage c. 1% recombination frequency corresponds to a map distance of 1cM (centiMorgan) d. Recombination between linked loci may occur during prophase I e. all of the above
c
Which of the following is false? a. In a nucleic acid double helix pyrimidine always pairs with a purine. b. DNA duplex with high A-T content is easier to denature than if it was higher in G-Cs c. The double helix of DNA under physiological conditions is usually in the A-form. d. All nucleic acids with complementary sequences can form duplexes under appropriate conditions. e. none of the above
e
Which of the following is false? a. In a nucleic acid double helix pyrimidine always pairs with a purine. b. DNA duplex with high A-T content is easier to denature than if it was higher in G-Cs c. The double helix of DNA under physiological conditions is usually in the B-form. d. All nucleic acids with complementary sequences can form duplexes under appropriate conditions. e. none of the above
c
Which of the following is false? a. In a nucleic acid double helix pyrimidine always pairs with a purine. b. DNA duplex with high G-C content is more difficult to denature than if it was higher in A-Ts c. The double helix of DNA is always in the B-form. d. All nucleic acids with complementary sequences can form duplexes under appropriate conditions. е. none of the above
e
Which of the following is false? a. In bacteria mRNA is frequently composed (exclusively) only of coding region b. All eukaryotic genes contain introns c. Eukaryotic transcription and translation occur at the same time because they take place in same cellular compartment d. All MRNAS include noncoding leader and trailer sequences (5' and 3'UTRS) e. a, b and c
b
Which of the following is false? a. Introns are removed by the process of RNA splicing, which generally occurs in cis on an individual RNA molecule. b. Most of the mutations in introns will affect protein sequence c. Mutations in introns may affect processing of the RNA and therefore prevent production of a "normal" protein. d. All of the above e. None of the above
e
Which of the following is false? a. Most genes are uninterrupted in yeast, but are interrupted in higher eukaryotes. b. Exons of interrupted genes are usually short, typically coding for less than 100 amino acids. c. Introns are short in lower eukaryotes, but range up to several 10s of kb in length in higher eukaryotes d. The overall length of a long interrupted gene depends to a large extent on the length and the # of introns. e. None of the above because they are all true in
e
Which of the following is false? a. Null mutations are loss-of-function mutations b. A point mutation in a coding region may be silent. c. Null allele may result from a deletion of the gene d. Several variants of the same gene are called multiple alleles e. None of the above
b
Which of the following is false? a. Null mutations are loss-of-function mutations b. A point mutation in a coding region may never be silent c. Null allele may result from a deletion of the gene d. Several variants of the same gene are called multiple alleles e. None of the above
b
Which of the following is false? a. There are three possible reading frames for any nucleic acid strand that would usually encode three entirely different protein sequences b. A deletion of three nucleotides within the gene's coding region will usually result in a frameshift mutation c. For most mRNAs only one of the reading frames is OPEN; an ORF d. An ORF (in most cases) starts with AUG and continues in triplets to a termination codon e. Blocked reading frames are interrupted by frequent termination (stop) codons
a
Which of the following is inconsistent with Central Dogma a. transfer of information into RNA is irreversible b. information in nucleic acids can be perpetuated c. information in proteins cannot be perpetuated d. transfer of information into protein is irreversible
e
Which of the following is inconsistent with the Central Dogma a. information in nucleic acids can be perpetuated b. information in proteins can be perpetuated c. transfer of information into RNA is irreversible d. transfer of information into protein is irreversible e. both b. and c.
c
Which of the following is inconsistent with the Central Dogma a. information in nucleic acids can be perpetuated b. information in proteins cannot be perpetuated c. transfer of information into RNA is irreversible d. transfer of information into protein is irreversible e. None of the above, because they are all consistent with the Central Dogma
d
Which of the following is inconsistent with the Central Dogma a. information in nucleic acids can be perpetuated b. information in proteins cannot be perpetuated c. transfer of information into RNA is reversible d. transfer of information into protein is reversible e. None of the above
a
Which of the following is not a part of every amino acid? a. hydroxyl group b. hydrogen c. amino group d. alpha C e. carboxyl group
e
Which of the following is true about a complementation test? a. It is used to determine if two mutations with similar phenotypes are in the same gene b. If the progeny of two homozygous (mutant) parents all have mutant (not wild type) phenotype the two mutations are probably in the same complementation group. c. Mutations that complement one another are said to be in the same complementation group. d. All of the above e. a. and b. only
d
Which of the following is true about core histone tails? a. Their lysines may be acetylated by HATS b. They may be phosphorylated by kinases c. They comprise about a 1/4 of the entire protein d. All of the above e. None of the above
d
Which of the following is true? a. In bacteria mRNA is frequently composed (exclusively) only of coding region b. All eukaryotic genes contain introns c. Eukaryotic transcription and translation occur at the same time because they take place in same cellular compartment d. All MRNAS include noncoding leader and trailer sequences (5' and 3'UTRS) e. None of the above
e
Which of the following is/are false about DNA replication? a. DNA replication may be unidirectional or bidirectional. b. In unidirectional replication there is only one replication eye whereas in bidirectional replication there are two c. In unidirectional replication only one strand of DNA is replicated whereas in bidirectional replication both strands are replicated. d. none of the above. e. both b. and c. are false.
e
Which of the following is/are false about DNA replication? a. In unidirectional replication there is only one replication b. DNA replication of bacterial genomes is unidirectional. c. In bidirectional replication both strands are replicated but in unidirectional replication only one strand is replicated. fork whereas in bidirectional replication there are two. d. all of the above. e. b. and c. only
a, f
Which of the following is/are false? Select all that apply. a. The double helix of DNA under physiological conditions is usually in the A-form. b. In a nucleic acid double helix pyrimidine always pairs with a purine. c. DNA duplex with higher G-C vs A-T content is more stable because it contains more hydrogen bonds. d. The double helix of DNA under physiological conditions is usually in the B-form. e. All nucleic acids with complementary sequences can form duplexes under appropriate conditions. f. The double helix of DNA under physiological conditions is usually in the Z-form.
d
Which of the following nucleotide sequences represents the complement to following polynucleotide sequence: 5 AGATCCG- 3'? a. 5'- AGATCCG- 3' c. 5'- AGAUCCG- 3 e. 5'- TCTAGGC- 3' b. 3' - AGATCCG- 3' d. 5- CGGATCT- 3'
d
Which of the following nucleotide sequences represents the complement to following polynucleotide sequence: 5' - AGATCCG- 3'? a. 5' - AGATCCG- 3' c. 5'- AGAUCCG- 3' e. 5'- TCTAGGC- 3 b. 3' - AGATCCG- 5' d. 5'- CGGATCT- 3'
a
Which of the following nucleotide sequences represents the complement to following polynucleotide sequence: 5' - AGATCCG- 3'? a. 5' - CGGATCT- 3' b. 5' - AGATCCG- 3' c. 3' - AGATCCG- 5' d. 5' - AGAUCCG- 3' e. 5' - TCTAGGC- 3'
e
Which of the following statements does not apply to the Watson and Crick model of DNA? a. The two antiparallel strands of the DNA form a double helix. b. The distance between the strands of the helix is uniform. c. The framework (backbone) of the helix consists of sugar-phosphate units of the nucleotides. d. The two strands of the helix are held together by hydrogen bonds. e. The purines form phosphodiester bonds with pyrimidines.
d
Which of the following statements regarding CDNA libraries is false? a. They include only the expressed portions of the genome. b. They are composed of DNA synthesized with the use of reverse transcriptase. c. They are composed of DNA synthesized using RNA templates. d. They contain introns and exons. e. None of the above.
b
Which type of a mutation would be most likely to have a catastrophic effect on the functioning of a protein? a. a base substitution at the beginning of the coding region b. a base deletion at the beginning of the coding region c. a base deletion near the end of the coding sequence d. deletion of three bases near the start of the coding sequence, but not in the initiator codon e. a base insertion near the end of the coding sequence
b
Which type of a mutation would be most likely to have a catastrophic effect on the functioning of a protein? a. a base substitution at the beginning of the coding region b. a base deletion at the beginning of the coding region с. a base deletion near the end of the coding sequence d. deletion of three bases near the start of the coding sequence, but not in the initiator e. a base insertion near the end of the coding sequence
d
Which type of a mutation would be most likely to have a catastrophic effect on the functioning of a protein? a. a transition in the third position of the codon at the beginning of the coding region b. a transversion near the end of the coding sequence. c. a base deletion near the end of the coding region. d. a base insertion near the beginning of the coding region. e. a deletion of three bases near the beginning of the coding region.
d
Why do eukaryotic cells have multiple initiation sites in their DNA unlike bacteria that usually have only one? a. Multicellular eukaryotes can have 1000 times the amount of DNA as bacteria. b. Eukaryotic cells incorporate nucleotides lower rates. c. Eukaryotic Okazaki fragments are 10 times shorter. d. All of the above e. a and c only
b
Why is an intact, linear double helix (with blunt ends) an ineffective template for DNA polymerase? a. It lacks a 3'-hydroxyl group, but has a template. b. It has a 3'-hydroxyl group, but lacks a template. c. It lacks a 3'-hydroxyl group and a template. d. It has a 3'-hydroxyl group and has a template. e. It lacks a 5'-hydroxyl group and has a template.
c
Why is an intact, linear double helix an ineffective template/substrate for DNA polymerase? a. It lacks a 3'-hydroxyl group and a template. b. It lacks a 3'-hydroxyl group, but has a template. c. It has a 3'-hydroxyl group, but lacks a template. d. It has a 3'-hydroxyl group and has a template. e. It lacks a 5'-hydroxyl group and has a template.
b
Why is an intact, single stranded circular DNA an ineffective template for DNA polymerase? a. It lacks a 3-hydroxyl group and a template. b. It lacks a 3-hydroxyl group, but has a template. c. It has a 3'-hydroxyl group, but lacks a template. d. It has a 3'-hydroxyl group and has a template. e. It lacks a 5'-hydroxyl group and a template.
d
Why is only one strand of DNA (of each gene) transcribed into mRNA? a. Because mRNA is only required in small quantities. b. Because the other strand is translated directly into a polypeptide. c. Because the other strand would produce mRNA coding the same amino acid sequence but in reverse order. d. Because transcribing both DNA strands would produce mRNA molecules coding for entirely different amino acid sequences. e. None of the above
d
__ are DNA unwinding enzymes that unwind the DNA in a reaction using the energy from __ to break the holding the two strands together. a. DNA helicases, ATP dehydration, disulfide linkages b. DNA gyrases, ATP hydrolysis, H bonds c. DNA helicases, ATP hydrolysis, 3'-5'-phosphodiester linkages d. DNA helicases, ATP hydrolysis, H bonds e. DNA gyrases, ATP dehydration, H bonds
a
cis-acting site a. may be a nontranscribed control region of a gene b. when mutated it generally affects the function of many genes that may be located. on different chromosomes c. frequently affects the function of the DNA with which it is not contiguous d. all of the above are true e. only a. and c. are true