Answer Key
Chapter Test B
Multiple Choice
1.
2.
3.
4.
5.
6.
7.
b
a
c
b
d
c
a
8.
9.
10.
11.
12.
13.
14.
15.
c
a
a
d
b
c
d
b
Copyright by McDougal Littell, a division of Houghton Mifflin Company
Short Answer
16. translation; cytoplasm
17. Structure 1 is an amino
acid, which will form a
peptide bond with another
other amino acid during
the translation process,
forming protein.
18. 4; UAC
19. Ribosome; the small
ribosomal unit binds to
mRNA in the cytoplasm.
The binding attracts a
tRNA with methionine to
the start codon. Then the
large ribosomal unit joins
in. The ribosome pulls the
mRNA through, adding
amino acids, and forms
peptide bonds between the
amino acids.
20. Sample answer: The
diagram would show
mRNA leaving the nucleus,
where transcription and
mRNA processing took
place. It would show
the amino acids chains
getting longer as translation
progressed. It also would
show tRNA leaving the
ribosome after translation
to collect more free-floating
amino acids. Finally, it
would show the ribosome
encountering a stop codon,
the peptide strand being
released, and the ribosome
disassembling.
21. frameshift mutation,
insertion of uracil
22. The reading frame is
thrown off because all of
the nucleotides are shifted
to the right. This change
will result in codons that
code for different amino
acids.
23. Sample answer: It would
probably have a lesser
effect on the organism
than a frameshift mutation,
because an incorrect amino
acid might have little effect
on a protein if it has about
the same size and the same
polarity as the original
amino acid or if it is far
from an active site.
24. Yes, if the error occurred in
a germ cell, the offspring
could be affected.
25. Yes, this mutation could
be caused by UV light,
industrial chemicals, or
pesticides.
Answer Key
1
CHAPTER
8
FROM DNA TO PROTEINS
Chapter Test B
Multiple Choice
Choose the letter of the best answer. (15 credits)
1. Which scientist used chemical analysis
to show that the genetic material in
bacteria is DNA?
a. Martha Chase
5. Suppose you can read the sequence of
bases on only one strand of the double
helix. What would you use to figure out
the sequence on the other strand?
b. Oswald Avery
a. central dogma
c. Frederick Griffith
b. x-ray crystallography
d. Alfred Hershey
c. Chargaff’s rules
d. base pairing rules
2. How did Hershey and Chase’s use of
radiolabeled bacteriophages to study
the genetic material validate Avery’s
research?
a. It demonstrated conclusively that the
Copyright © McDougal Littell/Houghton Mifflin Company.
3. Figure 8.1 shows a single strand of
DNA. Identify the nucleotide sequence
of the other DNA strand.
DNA replication in eukaryotes?
a. cytoplasm
c. nucleus
b. ribosome
d. vacuole
7. What does DNA polymerase do during
replication?
a. binds nucleotides together and
corrects base pair errors
b. transmits messages that are
translated into proteins
c. attracts amino acids to the ribosomes
for assembly
d. recognizes and points out new
origins of replication
CHAPTER 8
From DNA to Proteins
genetic material is not protein.
b. It showed that bacteriophages are not
digested by bacterial enzymes.
c. It proved that bacteria will take up
phosphorus, but not sulfur.
d. It confirmed that bacteriophages
cannot inject radiolabeled DNA.
6. Which of the following is the site of
C C G T A C T
FIG. 8.1
a. GGCUTGU
c. GGCATGA
b. AATGCAG
d. TTACGTC
4. The DNA double helix model used
today is the product of research done by
scientists
a. Hershey and Chase.
b. Watson and Crick.
c. Pauling and Franklin.
d. Chargaff and Griffith.
Assessment Book
McDougal Littell Biology
Chapter Test B
159
CHAPTER TEST B, CONTINUED
8. Figure 8.2 shows a single strand of
DNA. Identify the nucleotide sequence
of the complementary RNA strand.
T A G A G T C
FIG. 8.2
12. How many amino acids are coded for
in the following sequence of mRNA
nucleotides? Assume the reading
frame begins with the first nucleotide.
CGAUACAGUAGC
a. 3
c. 6
b. 4
d. 12
a. ATUTUAG
b. CAAGACT
c. AUCUCAG
d. ATCTCAG
13. When does mRNA processing take
place?
a. after replication
b. after translation
9. What "message" does mRNA carry?
a. the genetic code that, when
translated, forms proteins
b. orders for making ribosomes, a cell’s
protein factories
c. the order of base pairs in
complementary RNA strands
d. the number of codons in an
individual reading frame
c. after transcription
d. after protein synthesis
14. The nucleotide sequences that are
removed during mRNA processing are
called
a. operators.
c. exons.
b. promotors.
d. introns.
gene regulation occurs in
a. once in every cell cycle
a. yeasts.
c. humans.
b. when nucleotides float in the nucleus
b. bacteria.
d. eukaryotes.
Copyright © McDougal Littell/Houghton Mifflin Company.
CHAPTER 8
From DNA to Proteins
15. The lac operon is an example of how
10. When does replication occur?
c. during the cell’s M phase
d. when tRNA unzips DNA
11. Crick’s central dogma of molecular
biology is essentially a summary of
a. base pairing rules for all nucleotides.
b. genetic code stored in all start
codons.
c. amino acid relationships to
ribosomes.
d. replication, transcription, and
translation.
160
Chapter Test B
Assessment Book
McDougal Littell Biology
CHAPTER TEST B, CONTINUED
Short Answer Use the diagram below to answer items 16–20. (5 credits)
1
2
5
3
4
FIG. 8.3
16. Name the process shown in Figure 8.3 and identify the part of the cell where it takes
place.
17. Identify the structure labeled 1 in the diagram and describe its function.
Copyright © McDougal Littell/Houghton Mifflin Company.
the start codon. Then, write the nucleotide sequence for the corresponding anticodon.
19. Identify the structure labeled 5 in the diagram and describe its two-part role in forming a
polypeptide chain.
CHAPTER 8
From DNA to Proteins
18. Suppose translation has just begun. Write the number in the diagram that corresponds to
20. Suppose you could extend this diagram in both directions; predict what you would see.
Assessment Book
McDougal Littell Biology
Chapter Test B
161
CHAPTER TEST B, CONTINUED
Use the diagram below to answer items 21–25. (5 credits)
U
A U G U A A G U U U G G C
Met
Lys
Phe
Gly
FIG. 8.4
21. What type of error does Figure 8.4 show?
22. How is the reading frame affected by this error?
23. Suppose a nucleotide actually replaced another nucleotide in the figure above. Would
24. Could an error such as the one shown above affect the offspring of the organism in
which the error occurred?
25. Could an environmental mutagen cause this error? Give two examples to support
your answer.
162
Chapter Test B
Assessment Book
McDougal Littell Biology
Copyright © McDougal Littell/Houghton Mifflin Company.
CHAPTER 8
From DNA to Proteins
this change have a greater or lesser effect on the organism than that illustrated in the
figure? Explain.