Chapter 17 and 18 Mastering Biology
_____ bind(s) to DNA enhancer regions. - ANS-Activators
Activators are a type of transcription factor that bind to enhancer regions.
\A _____ mutation causes a wild-type amino acid to be replaced by a different amino acid -
ANS-missense
\A ______mutation causes an early Stop codon to occur. - ANS-nonsense
\A codon consists of _____ bases and specifies which _____ will be inserted into the
polypeptide chain. - ANS-three... amino acids
\A high concentration of bicoid protein at the opposite ends of a developing Drosophila
embryo would result in the development of a _____. - ANS-two headed fly
\A knock-out mutation refers to the loss of a protein's function but not necessarily to its
complete absence. - ANS-
\A particular triplet of bases in the template strand of DNA is 5-AGT-3. What would be the
corresponding codon for the mRNA that is transcribed? - ANS-3-UCA-5
\A________ does not change the wild-type amino acid sequence. - ANS-silent mutation
\Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on
specificity in the _____. - ANS-binding of the anticodon to the codon and the attachment of
amino acids to tRNAs
\At which site do new aminoacyl tRNAs enter the ribosome during elongation? - ANS-A site
\Bicoid mRNA is translated in _____. - ANS-fertilized egg
\DNA does not store the information to synthesize which of the following? - ANS-organelles
\DNA methylation and histone acetylation are examples of which of the following processes?
- ANS-epigenetic phenomena
\DNA methylation is a mechanism used by eukaryotes to do what? - ANS-inactivate genes
DNA methylation, involving the attachment of methyl groups to certain bases, is a
mechanism for the long-term inactivation of genes during development
\During RNA processing a(n) _____ is added to the 3' end of the RNA. - ANS-a long string of
adenine nucleotides
\During RNA processing a(n) _____ is added to the 5' end of the RNA. - ANS-modified
guanine nucleotide
\During the elongation phase of translation, which site in the ribosome represents the
location where a codon is being read? - ANS-A site
\Forms of the Ras protein found in tumors usually cause which of the following events to
occur? - ANS-excess cell division
\Gene expression is often assayed by measuring the level of mRNA produced from a gene.
What level of the control of gene expression can by analyzed by this type of assay? -
ANS-transcriptional control
\How do master regulatory genes function in cell differentiation? - ANS-They produce
proteins that act as transcription factors to produce proteins specific to the function of the
particular cell type.
They are often capable of changing some fully differentiated cells of different types into their
particular cell type.
, They may produce proteins that stimulate production of more of the master regulatory gene.
The transcription factors they produce coordinately control related genes.
\How does the primary transcript in a prokaryotic cell compare to the functional mRNA? -
ANS-the primary transcript is the same size as the mRNA
\How does the primary transcript in the nucleus of a eukaryotic cell compare to the functional
mRNA? - ANS-the primary transcript is larger than the mRNA
\If a DNA sequence is altered from TAGCTGA to TAGTGA, what kind of mutation has
occurred? - ANS-deletion
\If a mutated DNA sequence produces a protein that differs in one central amino acid from
the normal protein, which of the following kinds of mutations could have occurred? - ANS-an
addition mutation and a deletion mutation
\If the sequence ATGCATGTCAATTGA were mutated such that a base were inserted after
the first G and the third T were deleted, how many amino acids would be changed in the
mutant protein? - ANS-two
\In the structural organization of many eukaryotic genes, individual exons may be related to
which of the following? - ANS-the various domains of the polypeptide product
\initiation of translation - ANS-
\It is possible for a cell to make proteins that last for months; hemoglobin in red blood cells is
a good example. However, many proteins are not this long-lasting; they may be degraded in
days, hours, or even minutes. What is the advantage of short-lived proteins? -
ANS-Short-lived proteins enable the cells to control their activities precisely and efficiently.
\Polypeptides are assembled from _____. - ANS-amino acids
\Refer to the figure. Which of the triplets below is a possible anticodon for a tRNA that
transports proline to a ribosome? - ANS-3-GGC-5
\RNA processing converts the RNA transcript into _____. - ANS-mRNA
\Spliceosomes are composed of _____. - ANS-small RNAs and proteins
\Suppose that the triplet of nucleotides indicated in bold (AGC) spans two codons, that is,
CTA and GCC. If the triplet AGC were deleted from this DNA coding sequence, what effect
would it have on the resulting protein?
5'-ATGCTAGCCTATCGTAAC-3' - ANS-The two flanking codons would be altered, but the
rest of the amino acid sequence would be the same because there would be no frameshift.
\The bicoid gene is a type of _____ gene. - ANS-egg-polarity
\The bicoid gene is transcribed by _____. - ANS-nurse cells
\The bicoid gene product is directly responsible for _____ in a developing Drosophila
embryo. - ANS-the establishment of the anterior-posterior axis
\The direction of synthesis of an RNA transcript is _____. - ANS-5' --> 3'
\The initiator tRNA attaches at the ribosome's _____ site. - ANS-P
\The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single
codon. What is the result of this type of mutation? - ANS-polypeptide missing an amino acid
\The region of a Drosophila embryo with a low concentration of bicoid protein will develop
into the _____. - ANS-abdomen
\The region of a Drosophila embryo with the highest concentration of bicoid protein will
develop into the _____. - ANS-head
\The RNA segments joined to one another by spliceosomes are _____. - ANS-exons
\The tRNA anticodon, GAC, is complementary to the mRNA codon with the sequence
_____. - ANS-CUG
\The tRNA transfers an amino acid to the growing polypeptide chain. It is a molecule
involved in translation of mRNA. - ANS-
_____ bind(s) to DNA enhancer regions. - ANS-Activators
Activators are a type of transcription factor that bind to enhancer regions.
\A _____ mutation causes a wild-type amino acid to be replaced by a different amino acid -
ANS-missense
\A ______mutation causes an early Stop codon to occur. - ANS-nonsense
\A codon consists of _____ bases and specifies which _____ will be inserted into the
polypeptide chain. - ANS-three... amino acids
\A high concentration of bicoid protein at the opposite ends of a developing Drosophila
embryo would result in the development of a _____. - ANS-two headed fly
\A knock-out mutation refers to the loss of a protein's function but not necessarily to its
complete absence. - ANS-
\A particular triplet of bases in the template strand of DNA is 5-AGT-3. What would be the
corresponding codon for the mRNA that is transcribed? - ANS-3-UCA-5
\A________ does not change the wild-type amino acid sequence. - ANS-silent mutation
\Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on
specificity in the _____. - ANS-binding of the anticodon to the codon and the attachment of
amino acids to tRNAs
\At which site do new aminoacyl tRNAs enter the ribosome during elongation? - ANS-A site
\Bicoid mRNA is translated in _____. - ANS-fertilized egg
\DNA does not store the information to synthesize which of the following? - ANS-organelles
\DNA methylation and histone acetylation are examples of which of the following processes?
- ANS-epigenetic phenomena
\DNA methylation is a mechanism used by eukaryotes to do what? - ANS-inactivate genes
DNA methylation, involving the attachment of methyl groups to certain bases, is a
mechanism for the long-term inactivation of genes during development
\During RNA processing a(n) _____ is added to the 3' end of the RNA. - ANS-a long string of
adenine nucleotides
\During RNA processing a(n) _____ is added to the 5' end of the RNA. - ANS-modified
guanine nucleotide
\During the elongation phase of translation, which site in the ribosome represents the
location where a codon is being read? - ANS-A site
\Forms of the Ras protein found in tumors usually cause which of the following events to
occur? - ANS-excess cell division
\Gene expression is often assayed by measuring the level of mRNA produced from a gene.
What level of the control of gene expression can by analyzed by this type of assay? -
ANS-transcriptional control
\How do master regulatory genes function in cell differentiation? - ANS-They produce
proteins that act as transcription factors to produce proteins specific to the function of the
particular cell type.
They are often capable of changing some fully differentiated cells of different types into their
particular cell type.
, They may produce proteins that stimulate production of more of the master regulatory gene.
The transcription factors they produce coordinately control related genes.
\How does the primary transcript in a prokaryotic cell compare to the functional mRNA? -
ANS-the primary transcript is the same size as the mRNA
\How does the primary transcript in the nucleus of a eukaryotic cell compare to the functional
mRNA? - ANS-the primary transcript is larger than the mRNA
\If a DNA sequence is altered from TAGCTGA to TAGTGA, what kind of mutation has
occurred? - ANS-deletion
\If a mutated DNA sequence produces a protein that differs in one central amino acid from
the normal protein, which of the following kinds of mutations could have occurred? - ANS-an
addition mutation and a deletion mutation
\If the sequence ATGCATGTCAATTGA were mutated such that a base were inserted after
the first G and the third T were deleted, how many amino acids would be changed in the
mutant protein? - ANS-two
\In the structural organization of many eukaryotic genes, individual exons may be related to
which of the following? - ANS-the various domains of the polypeptide product
\initiation of translation - ANS-
\It is possible for a cell to make proteins that last for months; hemoglobin in red blood cells is
a good example. However, many proteins are not this long-lasting; they may be degraded in
days, hours, or even minutes. What is the advantage of short-lived proteins? -
ANS-Short-lived proteins enable the cells to control their activities precisely and efficiently.
\Polypeptides are assembled from _____. - ANS-amino acids
\Refer to the figure. Which of the triplets below is a possible anticodon for a tRNA that
transports proline to a ribosome? - ANS-3-GGC-5
\RNA processing converts the RNA transcript into _____. - ANS-mRNA
\Spliceosomes are composed of _____. - ANS-small RNAs and proteins
\Suppose that the triplet of nucleotides indicated in bold (AGC) spans two codons, that is,
CTA and GCC. If the triplet AGC were deleted from this DNA coding sequence, what effect
would it have on the resulting protein?
5'-ATGCTAGCCTATCGTAAC-3' - ANS-The two flanking codons would be altered, but the
rest of the amino acid sequence would be the same because there would be no frameshift.
\The bicoid gene is a type of _____ gene. - ANS-egg-polarity
\The bicoid gene is transcribed by _____. - ANS-nurse cells
\The bicoid gene product is directly responsible for _____ in a developing Drosophila
embryo. - ANS-the establishment of the anterior-posterior axis
\The direction of synthesis of an RNA transcript is _____. - ANS-5' --> 3'
\The initiator tRNA attaches at the ribosome's _____ site. - ANS-P
\The most commonly occurring mutation in people with cystic fibrosis is a deletion of a single
codon. What is the result of this type of mutation? - ANS-polypeptide missing an amino acid
\The region of a Drosophila embryo with a low concentration of bicoid protein will develop
into the _____. - ANS-abdomen
\The region of a Drosophila embryo with the highest concentration of bicoid protein will
develop into the _____. - ANS-head
\The RNA segments joined to one another by spliceosomes are _____. - ANS-exons
\The tRNA anticodon, GAC, is complementary to the mRNA codon with the sequence
_____. - ANS-CUG
\The tRNA transfers an amino acid to the growing polypeptide chain. It is a molecule
involved in translation of mRNA. - ANS-
