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KEY
Name ____________________________
PRACTICE TEST CHAPTER 13
Period ____ Date __________ Seat ____
______
B
1.
Which of the following describes RNA?
a.
b.
c.
d.
_______
2.
C
RNA is usually double-stranded and contains the base thymine.
RNA is usually single-stranded and contains the base uracil.
RNA is longer than DNA and uses five bases to encode information.
RNA is made in the nucleus of eukaryotic cells and stays there to carry out its functions.
The process by which the genetic code of DNA is copied into a strand of RNA is called
a. translation.
_______
3.
D
b. transformation
c. transcription
d. replication
In messenger RNA, each codon calls for a particular
a.
nucleotide
b. enzyme
c. promoter
d. amino acid
_______
4.
C
The process of making proteins on the ribosome based on instructions from messenger RNA is
called
a. transcription
b. transformation
c. translation
d. molecular biology
_______
D
5.
Changes in DNA sequences that affect genetic information are known as
a.
B
_______
6.
b. translations
c. transformations
toxin
b. mutagen
c. nucleotide
exons spliced together after introns are removed.
introns spliced together after exons are removed.
exons spliced together with introns.
long pieces of DNA shortened by the Dicer enzyme.
A mutation in which parts of a chromosome change direction is called a
a. inversion
_______
10.
B
c. is transcribed into RNA
d. is made of mRNA
In eukaryotes, functional messenger RNA molecules are made from
a.
b.
c.
d.
_______
9.
A
d. nitrogenous base
An expressed gene
a. functions as a promoter
b. codes for just one amino acid
_______
8.
A
d. mutations
A substance that can cause a change in the DNA code of an organism is called a
a.
C
_______
7.
replications
b. translocation
c. deletion
d. duplication
Because insertions and deletions within a gene result in a shift in the “reading frame” of the
genetic code, they are referred to as __ mutations.
a.
chromosomal
b. frameshift
c. sequence
1
d. codon
PRACTICE TEST CHAPTER 13
Use the codon chart below to answer questions 11—13.
C
_______
11.
Which of the following codons signifies the start and end of translation?
a.
_______
D 12.
CAA, UGA
c. AUG, UAG
d. UUU, GCA
Which of the chains of amino acids corresponds to the nucleotide sequence
UCAAGCGUA?
a. glu-cys-pro
C
_______
13.
b. UAA, ACU
b. glu-asp-“stop”
c. thr-arg-met
d. ser-ser-val
An anticodon that is complementary to the amino acid tyr (tyrosine) is
a. TUT
b. TUG
c. AUG
d. ATA
b. inversion
c. translocation
d. deletion
b. inversion
c. translocation
d. deletion
Use the diagrams below to answer questions 14—15.
_______
14.
B
Mutant 1 is a(n)
a. duplication
_______
A 15.
Mutant 2 is a(n)
a. duplication
2
PRACTICE TEST CHAPTER 13
16.
How does the enzyme that makes RNA “know” where to start transcribing the DNA?
The enzyme “knows” to start transcribing DNA at the promoter, which is a
region of DNA that has specific base sequences.
17.
Suppose you start with the DNA strand ACCGTCAC. What would a messenger RNA strand
Transcribed from this DNA strand look like?
The transcribed sequence would be UGGCAGUG.
18.
What is a codon?
A three base code “word” in the genetic code that specifies a particular
amino acid, start, or stop.
19.
How do anticodons work?
Each tRNA brings to the ribosome the amino acid specified by its complementary
codon. At the ribosome, anticodons in tRNA form bonds with the complementary
codons in mRNA, and tRNA adds its amino acid to the polypeptide chain.
20.
A code on a DNA molecule for a specific amino acid is CTA. What would the messenger RNA codon
be? What would the transfer RNA anticodon be?
Each tRNA brings to the ribosome the amino acid specified by its complementary
codon. At the ribosome, anticodons in tRNA form bonds with the complementary
codons in mRNA, and tRNA adds its amino acid to the polypeptide chain.
21.
Name and give examples of two major types of mutations.
Two major types of mutations are gene mutations and chromosomal mutations.
An example of a gene mutation is an insertion mutation, in which a single extra
base is inserted into a codon. An example of a chromosomal mutation is an
inversion, in which part of a chromosome is reversed.
22.
How does a deletion mutation differ from a substitution mutation?
A deletion mutation in a gene occurs when a base is lost from a codon. This shifts
the “reading frame,” so all the codons after the point of deletion are affected. A
substitution mutation occurs when a single base in a codon is replaced by a
different base. This does not shift the “reading frame.”
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PRACTICE TEST CHAPTER 13
23.
Can mutations have a positive effect? Explain your answer.
Mutations can have a positive effect. For example, a mutation could
produce a protein with a new or altered function that might be useful to
an organism in a changing environment.
Use the data table to answer questions 24—25.
24.
The table shows mRNA codons for three amino acids. Suppose a substitution mutation occurred
at the third nucleotide position of the codons for alanine. What would happen to the resulting
protein?
The mutation would have no effect because the codons would still code for
alanine.
25.
The three amino acids shown in the table have very similar—but not identical—properties. What
substitution mutations could cause one of these amino acids to be switched for another? What might
be the result?
A substitution mutation at the first or second nucleotide position of an alanine
codon will result in a different amino acid being placed in the sequence. For
example, if the second nucleotide position in alanine were switched from a C to
a U, then alanine would be replaced with valine.
With different amino acids, a protein might have a different structure and
function.
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