Download Unit 8 Exam - Protein Synthesis Bio Hrs

Unit 8: Protein Synthesis Exam – Biology Honors
Read each question carefully before selecting the best answer. You may use
more than one response, if needed.
Use this codon chart for questions that require it – good luck!
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Central Dogma of Genetics
1. It is thought that genes exert control in living organisms by
a. specifying polypeptide chains
b. interacting with proteins in the chromosome
c. sorting themselves independently in meiosis
d. interacting with enzymes in essential cell reactions
e. replicating themselves in mitosis
2. The sequence of nitrogen-containing bases on one strand of DNA most directly
determines the sequence of
a. fatty acids in a fat molecule
b. amino acids in a protein molecule
c. sugars in a polysaccharide molecule
d. bases in a protein molecule
3. The process of copying genetic material from DNA to RNA is called
a. translation
b. transformation
c. replication
d. transcription
e. polymerization
4. Which of the following molecules functions to transfer information from the nucleus
to the cytoplasm?
a. DNA
b. mRNA
c. tRNA
d. proteins
e. lipids
5. A gene may encode information needed by a cell to produce
a. enzymes
b. structural proteins
c. hormones
d. RNA
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Protein synthesis (transcription, editing, translation)
6. A transcription start signal is called
a. an initiation codon
b. a promoter
c. an origin
d. a start site
e. a nonsense codon
Select the molecule that best fits the numbered statement. Letters may be
used more than once or not at all:
a. tRNA
b. rRNA
c. RNA polymerase
d. mRNA
e. none of these
7. Carries the transcribed genetic code sequence
8. Has anticodons
9. Reads the codons to find a match
10. Contains codons
11. Attaches to specific amino acids
12. Contains no uracil
13. T/F: Each ribosome is specific for a particular type of protein
14. T/F: Each tRNA is used only once
15. Uracil pairs with
a. thymine
b. adenine
c. guanine
d. cytosine
e. uracil
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16. If a tRNA molecule specialized for transfer of the amino acid valine has the
anticodon CAG, with what codon will it couple?
a. GAC
b. GTC
c. TUG
d. GUC
e. CAG
Suppose one strand of a “mini-gene” has the following base sequence:
TACCCGGATTCA
17. The polypeptide encoded by this gene has how many amino acids?
a. 2
b. 4
c. 6
d. 12
18. The last codon in the mRNA transcribed from the DNA strand above will be
a. UGA
b. AGT
c. AGU
d. TCA
19. Which of the following represents the proper base pairing for DNA?
a. A-A, C-C
b. A-C, G-T
c. G-A; C-T
d. T-A; G-A
e. T-A; G-C
20. The actual assembly of amino acids into protein occurs on the
a.
endoplasmic reticulum
b.
ribosomes
c.
tRNA
d.
Golgi bodies
e.
None of the above.
21. One DNA codon consists of _____nucleotide(s) that code (s) for _______amino
acid(s).
a.
one; one
b.
one; three
c.
three; three
d.
two; four
e.
three; one
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Given the sequence: GTAGTAGGT
22. What would be the sequence of bases of an mRNA molecule that was transcribed
from the sequence of DNA bases shown above?
a.
GTAGTAGGT
b.
CAUCAUCCA
c.
AUGAUGAAU
d.
UCGUCGUUC
e.
CATCATCCA
23. Which
a.
b.
c.
d.
of the following nitrogen bases is found in RNA but not in DNA?
adenine
cytosine
guanine
uracil
24. What is an anticodon part of?
a.
DNA
b.
tRNA
c.
rRNA
d.
mRNA
25. Which of the following represents a difference between RNA and DNA?
a. RNA is single stranded
b. RNA contains the sugar ribose
c. RNA utilizes nucleotides in its structure
d. RNA substitutes uracil for thymine
26. Which of the following types of RNA carries amino acids to ribosomes where the
amino acids are joined to make a polypeptide?
a. mRNA
b. tRNA
c. rRNA
d. nRNA
27. Which of the following is NOT found in mRNA that has completed posttranscriptional modification?
a. a methylated cap
b. introns
c. exons
d. the poly-A tail
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A DNA strand has this base sequence: A_C_G_T_A_C
28. The matched DNA strand in the helix will have the base sequence:
a. A C G T A C
b. T G C A T G
c. T U C A T U
d. U G C A U G
e. T G U A T G
29. Each new amino acid is attached to the growing chain by
a. an ionic bond
b. a physical bond
c. hydrogen bonds
d. an RNA bond
e. a peptide bond
Mutations - chromosomal and gene
30. The replacement of glutamic acid by valine at a specific position in the beta chains
of hemoglobin leads to sickle cell anemia. This change represents which of the following
mutational events?
a.
DNA base-pair substitution
b.
DNA base-pair deletion
c.
DNA base-pair addition
d.
Chromosomal deletion
e.
Frame shift mutation
A portion of the genetic code is:
UUU=phenylalanine
GCC=alanine
AAA=lysine
CCC=proline.
31. Assume the correct code places the amino acids phenylalanine, alanine, and lysine
in a protein (in that order). Which of the following DNA changes would substitute
proline for alanine?
a. AAACGGTTA
b. AATCGGTTT
c. AAACCGTTT
d. AAAGGGTTT
e. none of the above
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32. Which of the following DNA mutations represent the MOST potentially damaging to
the protein it codes for?
a. a base pair deletion
b. a codon substitution
c. a substitution in the last base of a codon
d. a codon deletion
For the next two questions, refer to the chart below.
mRNA Codons
Amino acids
AGA
arginine
GGA
glycine
AGC
serine
GCA
alanine
CAG
glutamine
glutamine - glutamine - glutamine
serine - serine – serine
33. Which of the following messenger RNA sequences could code for both of the two
amino acid sequences above, simply by a shift in the reading frame?
a. AGCAGCAGCAGC
b. AGUAGUAGUAGU
c. CAACAACAACAA
d. GCUGCUGCUGCU
e. GCAAGCGCAAGC
glycine-serine-glycine
34. Which of the following DNA strands will code for the amino acid sequence shown
above?
a. ACTCCTTCT
b. TCTCCGTCG
c. CCGTCGACT
d. CCTCCGTCG
e. CCTTCGCCT
ABCDEF ----> ABDCEF
35. A rearrangement in the linear sequence of genes as shown above is known as
a. duplication
b. deletion
c. inversion
d. polyploidy
e. translocation
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36. A single substitution in the third position would have the greatest probability of
mutational effect on the codon
a. GUU
b. AUU
c. CGU
d. AUG
e. CCC
37. Which amino acid has the greatest number of codons?
a. Leucine (leu)
b. Proline (pro)
c. Tryptophan (trp)
d. Glutamic acid (glu)
e. Aspartic acid (asp)
38. Some geneticists consider the third base of a codon to be less important than the
first two bases as a code for a specific amino acid. All of the following observations
would support this hypothesis EXCEPT
a. any of the bases following a CC- sequence will position a proline.
b. even though the A is replaced by a C, the triplet AGG will still position to an
arginine
c. Even though the last A is replaced by a G, the triplet UAA will still terminate a
polypeptide chain.
d. An AUU triplet codes for isoleucine, while a UUU triplet codes for
phenylalanine.
e. there are three codons, any of which will position an isoleucine
Consider the following diagram:
enzyme a
enzyme b
A -----------------------------------> B ----------------------------------> C
39. A mutation results in a defective enzyme a. Which of the following would be a
consequence?
a. an accumulation of A and no production of B and C
b. an accumulation of A and B and no production of C
c. an accumulation of B and no production of A and C
d. an accumulation of B and C and no production of A
e. an accumulation of C and no production of A and B
40. Which type of mutation is potentially heritable?
a. Chromosomal mutation
b. gene mutation
c. neither
41. T/F: 99.9% of mutations are believed to be repaired by the cell
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42. What type of cell must be mutated in order for a mutation to be heritable?
a. germ line cell
b. body cell
c. mature
d. none of these
43. Which of the following is NOT considered to be a potential mutagen?
a. infrared radiation
b. ultraviolet radiation
c. strong chemicals
d. X-Rays
Eukaryotic Gene Regulation - 4 major areas
44. Your tongue does not grow hair because
a. different genes are expressed in different tissues
b. skin cells have extra DNA that codes for hair proteins
c. the genes for hair proteins have been deleted from the cells of your tongue
d. saliva prevents hair from forming
e. none of the above
45. Gene expression in eukaryotes may depend upon
a. the position of the gene on the chromosome.
b. the state of the external environment
c. the stage of development of the organism
46. At
a.
b.
c.
d.
e.
what level(s) can transcription be regulated in eukaryotic cells?
individual genes
regions of chromosomes
entire chromosomes
all of the above
none of the above
47. T/F: Exon splicing allows both prokaryotes and eukaryotes to modify the genes
expressed
48. mRNA can be modified in several ways. Which of the following are potential
methods?
a. methylated Guanine cap
b. regulator genes produce repressor proteins
c. poly-A tail
d. exon splicing
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49. Environmental stimuli helps regulate gene expression in eukaryotes. Which of the
following would qualify as activators for gene expression?
a. hormones
b. stress
c. heat
d. none of these
50. If the structure of a TV show is analogous to the structure of a gene, then the
introns of a gene would be analogous to
a. the opening theme music
b. the segments of the show
c. the commercials between segments of the show
d. the commercials between shows
e. the closing credits
51. T/F: All cells in the body have the potential to produce the same sets of proteins
Prokaryotic Gene Regulation - the operon
If gene regulation of the lac operon in a prokaryote is compared to the operation of a
thermostat-controlled air conditioner, match the event in the cell with the event in the
thermostat.
52. Temperature rises
a. repressor protein binds to operator region
53. Thermostat triggers air
again
conditioning
b. lactose levels increase in cell
54. Air temperature drops
c. lactose metabolized
55. Air conditioner shuts off
d. lactose removes repressor protein; RNA
polymerase gains access to promoter
56. Which gene produces the repressor protein?
a. promoter
b. regulator
c. operon
d. operator
57. What is the purpose of the inducer in the prokaryotic operon?
a. activates the repressor
b. deactivates the repressor
c. neither
d. both
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58. Which of the following might be seen as an advantage of the operon regulatory
system?
a. allows the cell to be efficient in its production of proteins
b. allows the cell to activate or deactivate a group of genes at the same time
c. allows eukaryote to regulate gene expression
d. none of these
59. Which analogy is most appropriate in describing the function of an operon?
a. a circuit breaker
b. a light switch
c. a key
d. a lock
60. T/F: The lac operon would be considered positive gene regulation, and the trp
operon would be considered negative gene regulation
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