Download Quiz #6 - San Diego Mesa College

MESA COLLEGE, SAN DIEGO
School of Mathematics & Natural Sciences
General Biology Lecture (BIOL 107)
Instructor: Elmar Schmid, Ph.D.
QUIZ #6
DNA
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Answer the following questions of this ‘open book, open notes and free access instructor
website’ quiz and mark it on a Scantron 882-E answer sheet.
All questions must be answered by the student without help by class mates, friends or
other human beings. Please read the following statement below carefully and sign it if you
satisfy the guidelines outlined in this statement. This signed take home exercise sheet
must be turned in with your answer sheet to receive full credit for this assignment. This
assignment is due at the first class meeting the following week.
I HAVE ANSWERED THE QUESTIONS IN THIS EXERCISE ON MY OWN. I DID NOT CONSULT OTHERS
OR IN ANY CONDUCT IN ANY ACTIVITITES THAT COULD BE CONSTRUED AS CHEATING IN THIS
ASSIGNMENT. I DID NOT MAKE ANY COPIES OF THIS ASSIGNMENT.
_________________________________
(PRINT YOUR NAME)
________________________________
(YOUR SIGNATURE)
Q. 1: Where on a DNA strand does DNA replication start?
A) at the site of origin (ori)
B) at a promoter region
C) at the centromere region
D) anywhere along a DNA strand
Q. 2: The double helix of the DNA molecule can be relatively easy separated into its two polynucleotide
strands during DNA replication, because the paired bases of its nucleotides are held together by polar
covalent bonds.
A) True
B) False
Q. 3: A segment of nucleotide sequence on the DNA double helix which encodes the genetic information
for either one protein or enzyme is called:
A) a genome
B) a gene
C) an operon
D) a chromosome
E) a sister chromatid
Q. 4: The 3-prime (5’) end of a DNA molecule refers to
A) its end with a free (unreacted) phosphate group
B) its end with a free (unreacted) hydroxyl group of the deoxyribose sugar
C) its end with a free (unreacted) hydroxyl group of the ribose sugar
Q. 5: The second event of DNA replication occuring at the DNA double helix is
A) the binding of the RNA polymerase
B) the local unwinding of the two DNA molecules by the helicase enzyme
C) the binding of the DNA polymerase
D) the pairing (= annealing) of the Okazaki fragments
E) the formation of the replication fork
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MESA COLLEGE, SAN DIEGO
School of Mathematics & Natural Sciences
General Biology Lecture (BIOL 107)
Instructor: Elmar Schmid, Ph.D.
Q. 6: On the newly forming daughter strand, DNA polymerization proceeds in ___________ direction.
A) 5’ – 3’
B) 3’ – 5’
C) any of the above
Q. 7: The short RNA pieces the DNA polymerase needs to successfully start DNA replication, are
called:
A) plasmids
B) primers
C) Okazaki fragments
D) tRNA
E) rRNA
Q. 8: A change of the genetic information of the DNA molecule due to a variation of the nucleotide
sequence is called:
A) mutuality
B) mutation
C) base pairing
D) variation
E) a and b
Q. 9: Multiple origins of replication on the DNA molecule of eukaryotic cells serve to
A) remove any errors in replication that occur
B) create multiple copies of the DNA molecule at the same time
C) shorten the duration of time necessary for DNA replication
D) reduce the number of “replication bubbles” that occur in the DNA double helix during replication
E) assure the correct orientation of the two strands in the newly growing double helix
Q. 10: Which of the following is a mutagen and (directly acting) carcinogen because it chemically
modifies certain bases in a DNA molecule upon encounter?
A) Benzo(a)pyren
B) the warfare poison Nitrogen mustard
C) Methylnitrosourea
D) urea
E) both, b and c
Q. 11: During DNA replication the replicating enzyme which adds new nucleotides to the template
DNA strand runs only on one strand with the opening replication fork. Which strand is this?
A) the single-stranded DNA
B) the leading strand C) the lagging strand
Q. 12: DNA transcription means
A) the doubling (= duplication) of a gene on the DNA strand
B) the copying of the genetic information on a gene into a double-stranded RNA molecule
C) the copying of the genetic information on a gene into a single-stranded RNA molecule
D) the copying of the genetic information on a gene into a polypeptide chain
E) the cutting-out (= excision) of non-coding DNA sequences from the DNA strand
Q. 13: The second event of DNA transcription is
A) initiation
B) translocation
C) elongation
D) termination
Q. 14: Where within an eukaryotic cell does DNA transcription takes place?
A) the nucleus
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MESA COLLEGE, SAN DIEGO
School of Mathematics & Natural Sciences
General Biology Lecture (BIOL 107)
Instructor: Elmar Schmid, Ph.D.
B) the cell membrane
C) the ribosome
D) the proteasome
Q. 15: Coding segments of a gene, which code for an enzyme or protein are called:
A) introns
B) silent mutations
C) operons
D) exons
E) enhancers
Q. 16: You are a Biochemist and you carefully isolated ribosomes from a living cell. Which of the
following cellular components would you very likely find to be attached with your ribosomal proteins?
A) rRNA, DNA, mRNA,
B) rRNA, pre-mRNA, aminoacyl-tRNA
C) rRNA, mRNA, aminoacyl-tRNA
D) tRNA, pre-mRNA, polypeptides
E) only mRNA and aminoacyl-tRNA
Bonus Q. 1: Experiments have demonstrated that the “words” of the genetic code (the units that
specify amino acids) are
A) three-nucleotide sequences (= triplets)
B) two-nucleotide sequences (= duplets)
C) single nucleotides
D) nucleotide sequences of various lengths
E) 3-carbon sugar molecules
Bonus Q. 2: How many stop codons are laid down in the genetic code of life?
A) 1
B) 2
C) 3
D) 61
E) countless
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