Download HA Nucleic Acids Practice Exam

HA Nucleic Acids Practice Exam
Multiple Choice
Identify the choice that best completes the statement or answers the question.
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1. Which series is arranged in order from largest to smallest in size?
a. chromosome, nucleus, cell, DNA, nucleotide
b. cell, nucleus, chromosome, DNA, nucleotide
c. nucleotide, chromosome, cell, DNA, nucleus
d. cell, nucleotide, nucleus, DNA, chromosome
Figure 12-2
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2. In which part of the cell does this process shown in Figure 12-2 take place?
a. in the nucleus
c. at the ribosomes
b. in food vacuoles
d. on the chromosome
3. Structure III in Figure 12-2 represents a(n) ____.
a. gene
c. codon
b. amino acid
d. DNA molecule
4. The process illustrated in Figure 12-2 is called ____.
a. translation
c. monoploidy
b. replication
d. transcription
5. Which of the structures in Figure 12-2 are composed of RNA?
a. II and IV
c. I and V
b. III and IV
d. III and V
6. A DNA segment is changed from-AATTAG- to -AAATAG-. This is a ____.
a. frameshift mutation
c. insertion
b. substitution
d. deletion
Figure 12-3
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7. What type of mutation has occurred in Figure 12-3?
a. substitution
c. lethal
b. frameshift
d. insertion
8. What will be the result of the mutation in Figure 12-3?
a. it will have no effect on protein function
b. only one amino acid will change
c. nearly every amino acid in the protein will be changed
d. translation will not occur
9. A DNA segment is changed from -AATTAGAAATAG- to -ATTAGAAATAG-. This is a ____.
a. frameshift mutation
c. inversion
b. insertion
d. translation
10. A particular sequence of parent DNA has four purine bases and two pyrimidine bases. According to base-pairing
rules, which of the following sequences could be formed during replication?
a. two cytosine, two adenine, two thymine
b. two cytosine, two adenine, two uracil
c. two adenine, two thymine, one guanine, one cytosine
d. two adenine, two guanine, two cytosine
11. Which of the following sequences of processes correctly reflects the central dogma?
a. protein synthesis, transcription, translation
b. protein synthesis, translation, transcription
c. transcription, translation, protein synthesis
d. translation, transcription, protein synthesis
12. Here are two related mRNA sequences: 5'UUUAGCGAGCAU3' and 5'UUUAGCCAUAAAAAAAA3'. How
was the second sequence formed?
a. a tandem repeat mutation formed the second sequence
b. processing removed an exon and added a poly-A tail to form the second sequence
c. processing removed an intron and added a poly-A tail to form the second sequence
d. RNA polymerase matched up several incorrect nucleotide bases to the original DNA as the
second sequence formed
13. Using DNA sequencing, you discover that a bacterium has experienced a deletion mutation that removed three
nucleotides. The bacterium appears completely unaffected in all its functions. Where is the mostly likely
location for the mutation?
a. an exon
c. a promoter
b. an intron
d. a repressor
14. DNA replication of a leading strand involves which enzymes?
a. primase, polymerase
b. primase, polymerase, ligase
c. helicase, primase, ligase
d. helicase, primase, polymerase, ligase
Problem
15. In Figure 12-5, use the letter P to label all of the phosphate groups. Use an S to label all the sugar molecules. For
labeling the nitrogen bases, use a T for thymine and a C for cytosine. Guanine and adenine have been filled in for
you. Circle and label a codon. Circle and label a nucleotide.
Figure 12-5
HA Nucleic Acids Practice Exam
Answer Section
MULTIPLE CHOICE
1. ANS: B
Nucleotides are the subunits of nucleic acids like DNA. DNA coils around histone proteins to form
chromosomes, which are contained in the nucleus of a cell.
Feedback
A
B
C
D
Chromosomes are in the nucleus.
That's correct!
Check page 329.
What is a chromosome made of?
PTS: 1
DIF: Bloom's Level B
NAT: LS_1c
TOP: 12-3
2. ANS: C
The process of translation takes place at the ribosomes.
REF: 329 | 332
Feedback
A
B
C
D
This process happens after messenger RNA leaves the nucleus.
Where does messenger RNA go when it leaves the nucleus?
That's correct!
Chromosomes are made up of DNA and proteins.
PTS: 1
DIF: Bloom's Level C
REF: 338
NAT: LS_1c
STA: 3.3
TOP: 12-6
3. ANS: B
A tRNA molecule carries a specific amino acid corresponding to the anticodon of that tRNA molecule.
Feedback
A
B
C
D
What is the definition of a gene?
That's correct!
You're on the right track, but the anticodon is located somewhere else on this molecule.
DNA does not have uracil as one of its bases.
PTS: 1
DIF: Bloom's Level C
REF: 338
NAT: LS_1c
STA: 3.3
TOP: 12-6
4. ANS: A
Translation is the process by which the mRNA “template” is used to form polypeptides.
Feedback
A
B
C
D
That's correct!
Page 334 shows replication.
Check the definition of monoploidy.
Is any DNA involved in the pictured process?
PTS: 1
NAT: LS_1c
5. ANS: A
DIF: Bloom's Level B
STA: 3.3
TOP: 12-6
REF: 338
The mRNA “template” and the tRNA molecule are the only RNA structures. I is an anticodon composed of
nucleotide bases, III is a polypeptide, and V is an amino acid.
Feedback
A
B
C
D
That's correct!
Only one of these is made of RNA.
What is an anticodon?
These are related to each other, but they are not made of RNA.
PTS: 1
DIF: Bloom's Level C
REF: 336 | 338
NAT: LS_1c
STA: 3.3
TOP: 12-6
6. ANS: B
The number and identities of the bases in the two sequences are the same except for the substitution of an
adenine molecule for a thymine.
Feedback
A
B
C
D
A frameshift mutation changes the number of bases in the sequence.
That's correct!
Do the two sequences contain the same number of bases?
Check page 346 for the definition of a deletion.
PTS: 1
DIF: Bloom's Level A
REF: 345
NAT: LS_2a | LS_2c
STA: 3.4
TOP: 12-11
7. ANS: B
Deleting a nucleotide causes a frameshift mutation, since the codons following the deletion will code for
different amino acids than the original sequence.
Feedback
A
B
C
D
Check the definition of a point mutation on page 345.
That's correct!
How do you know what effects the mutation has on the whole organism?
A protein is simply a polypeptide, or chain of amino acids.
PTS: 1
DIF: Bloom's Level A
REF: 346
NAT: LS_2a | LS_2c
STA: 3.4
TOP: 12-11
8. ANS: C
Since the reading “frame” is shifted one place, all amino acids after the deletion will be different from the
original sequence.
Feedback
A
B
C
D
Protein function is determined by the sequence of amino acids in the protein.
Look closely at the codons that follow the mutation.
That's correct!
Do you see a stop codon?
PTS: 1
DIF: Bloom's Level B
REF: 346
NAT: LS_2a | LS_2c
STA: 3.4
TOP: 12-11
9. ANS: A
The deletion of adenine from the beginning of the sequence causes a frameshift mutation.
Feedback
A
B
That's correct!
Is the number of nucleotides the same in the original and mutated sequences?
C
D
An inversion reverses the order of nucleotides.
Review the definition of translation on page 338.
PTS: 1
DIF: Bloom's Level B
REF: 345–346
NAT: LS_2a | LS_2c
STA: 3.4
TOP: 12-11
10. ANS: A
According to base-pairing rules, the number of purine bases formed must match the number of pyrimidine bases
in the parent sequence.
Feedback
A
B
C
D
That's correct!
Does uracil occur in DNA?
Count the number of purine bases.
Review base pairing rules on page 329.
PTS: 1
DIF: Bloom's Level E
REF: 329–330 | 333
NAT: LS_2a
STA: 3.1
TOP: 12-2
11. ANS: C
The central dogma states that DNA is transcribed to mRNA, which is translated to a sequence of amino acids
that form a polypeptide.
Feedback
A
B
C
D
The central dogma starts with DNA.
Check page 336.
That's correct!
What is the difference between transcription and translation?
PTS: 1
DIF: Bloom's Level B
NAT: LS_1c
STA: 3.2
TOP: 12-8
12. ANS: C
RNA processing removes introns and adds a poly-A tail.
REF: 336–339
Feedback
A
B
C
D
A tandem repeat is a set of copied codons.
Check the definition of exons on page 337.
That's correct!
Are the nucleotides in the second sequence unrelated to those in the first sequence?
PTS: 1
DIF: Bloom's Level D
REF: 337
NAT: LS_1c
STA: 3.2
TOP: 12-8
13. ANS: B
Introns, or intervening sequences, get processed out of the mRNA before it leaves the nucleus, so removal of an
intron would probably have little effect on bacterial functions such as enzyme synthesis.
Feedback
A
B
C
D
You're on the right track.
That's correct!
The promoter is involved in gene regulation.
What is a deletion?
PTS: 1
DIF: Bloom's Level E
NAT: LS_1d | LS_2c
STA: 3.4
14. ANS: D
REF: 337
TOP: 12-7
The leading strand is formed continuously, but since replication can originate at multiple points along the
chromosome, all four enzymes are needed.
Feedback
A
B
C
D
How does the DNA unwind?
Check page 334 for hints.
You're on the right track.
That's correct!
PTS: 1
NAT: LS_2a
DIF: Bloom's Level E
STA: 3.2
TOP: 12-5
REF: 334
PROBLEM
15. ANS:
See Solution 12-6.
PTS: 1
DIF: Bloom's Level C
NAT: LS_1c | LS_2a
STA: 3.1
REF: 329–330 | 338
TOP: 12-2