BIO 148 EXAM 2 PRACTICE
QUESTIONS & ANSWERS
Which of the following is part of a DNA molecule (i.e. is made up of DNA nucleotides)?
1. Promoter
2. Switch
3. Gene
4. 5' cap
5. Activator - Correct Answers -1, 2, and 3 only
A doctor is trying to identify the mutant gene that causes her patient to be colorblind. To
do this she takes a swab of the patient's cheek cells to send off for DNA sequencing.
Did she sample the correct cells? - Correct Answers -Yes, because both cells have the
same genes
RNA polymerase ________ - Correct Answers -Synthesizes a nucleic acid that is
complementary to the template strand
Why was there selection for loss of pelvic spine in freshwater environment? Why not
just keep the spine? - Correct Answers -There were predatory and energetic costs
(fitness disadvantages) to having a pelvic spine in the freshwater habitats.
True or false: The pelvic spine is an adaptation in all sticklebacks. - Correct Answers -
False
What caused the mutation in the pelvic switch? - Correct Answers -The mutation was
random and may have occurred in the ancestral population that got land-locked in the
lakes
For most multicellular organisms, how can the cells of a single organism have different
shapes and actions? - Correct Answers -They express different genes
An individual has a mutation in the gene that encodes a switch activator protein. The
mutation prevents the activator protein from binding to the switch that controls the
expression of the lactase gene. What will the ultimate outcome of this mutation be? -
Correct Answers -The lactase gene will not be transcribed so the mRNA will not be
translated
Within the eukaryotic cell, transcription occurs in the __________ and RNA splicing
occurs in the _____. - Correct Answers -Nucleus; nucleus
, The DNA molecules in eye cells contain which of the following?
-a.) Genes that encode eye color and skin color, and switches that control both eye
color and skin color
-b.) Genes that encode eye color and skin color, and switches that control eye color
only (not skin color)
-c.) Genes and switches that encode eye color only (not skin color)
-d.) Genes that control eye and skin color, but not switches for either of these genes. -
Correct Answers --A: Genes that encode eye color and skin color, and switches that
control both eye color and skin color
Which of the following is a part of a DNA molecule?
-a.) Promoter
-b.) Switch
-c.) Gene - Correct Answers --A: Promoter
-B: Switch
-C: Gene
How might a single base change (substitution) in the sequence of an exon affect the
protein encoded by the gene? - Correct Answers --A single amino acid could change
-The length of the polypeptide could change
-It is possible that the change would have no effect on the protein
Which of the following contains information that determines the amino acid sequence of
the protein encoded by this gene?
-a.) The gene's promoter
-b.) Nucleotides between +1 and the start codon
-c.) Nucleotides in exons - Correct Answers --C: Nucleotides in exons
A possible sequence of nucleotides in the template strand of DNA that would code for a
portion of a polypeptide with the amino acid sequence Phe-Ile would be _____.
-a.) 3' TTG-CTA 3'
-b.) 3' AAC-GAC 5'
-c.) 3' AUG-CTG 3'
-d.) 3' AAA-AAT 5'
-e.) 3' AAA-TAA 5' - Correct Answers --E: 3' AAA-TAA 5'
mRNA in eukaryotes - Correct Answers -It is produced in the nucleus, contains
untranslated sequences and is translated in the cytoplasm
What determines the tertiary structure of proteins? - Correct Answers -Genes determine
the amino acid sequence of the protein, which determines its tertiary structure
Which of the following mutations is the most likely to be deleterious?
-a.) A switch mutation that leads to increased fertility in females
-b.) A missense mutation that enhances the function of a protein
-c.) A frameshift mutation in an essential gene
QUESTIONS & ANSWERS
Which of the following is part of a DNA molecule (i.e. is made up of DNA nucleotides)?
1. Promoter
2. Switch
3. Gene
4. 5' cap
5. Activator - Correct Answers -1, 2, and 3 only
A doctor is trying to identify the mutant gene that causes her patient to be colorblind. To
do this she takes a swab of the patient's cheek cells to send off for DNA sequencing.
Did she sample the correct cells? - Correct Answers -Yes, because both cells have the
same genes
RNA polymerase ________ - Correct Answers -Synthesizes a nucleic acid that is
complementary to the template strand
Why was there selection for loss of pelvic spine in freshwater environment? Why not
just keep the spine? - Correct Answers -There were predatory and energetic costs
(fitness disadvantages) to having a pelvic spine in the freshwater habitats.
True or false: The pelvic spine is an adaptation in all sticklebacks. - Correct Answers -
False
What caused the mutation in the pelvic switch? - Correct Answers -The mutation was
random and may have occurred in the ancestral population that got land-locked in the
lakes
For most multicellular organisms, how can the cells of a single organism have different
shapes and actions? - Correct Answers -They express different genes
An individual has a mutation in the gene that encodes a switch activator protein. The
mutation prevents the activator protein from binding to the switch that controls the
expression of the lactase gene. What will the ultimate outcome of this mutation be? -
Correct Answers -The lactase gene will not be transcribed so the mRNA will not be
translated
Within the eukaryotic cell, transcription occurs in the __________ and RNA splicing
occurs in the _____. - Correct Answers -Nucleus; nucleus
, The DNA molecules in eye cells contain which of the following?
-a.) Genes that encode eye color and skin color, and switches that control both eye
color and skin color
-b.) Genes that encode eye color and skin color, and switches that control eye color
only (not skin color)
-c.) Genes and switches that encode eye color only (not skin color)
-d.) Genes that control eye and skin color, but not switches for either of these genes. -
Correct Answers --A: Genes that encode eye color and skin color, and switches that
control both eye color and skin color
Which of the following is a part of a DNA molecule?
-a.) Promoter
-b.) Switch
-c.) Gene - Correct Answers --A: Promoter
-B: Switch
-C: Gene
How might a single base change (substitution) in the sequence of an exon affect the
protein encoded by the gene? - Correct Answers --A single amino acid could change
-The length of the polypeptide could change
-It is possible that the change would have no effect on the protein
Which of the following contains information that determines the amino acid sequence of
the protein encoded by this gene?
-a.) The gene's promoter
-b.) Nucleotides between +1 and the start codon
-c.) Nucleotides in exons - Correct Answers --C: Nucleotides in exons
A possible sequence of nucleotides in the template strand of DNA that would code for a
portion of a polypeptide with the amino acid sequence Phe-Ile would be _____.
-a.) 3' TTG-CTA 3'
-b.) 3' AAC-GAC 5'
-c.) 3' AUG-CTG 3'
-d.) 3' AAA-AAT 5'
-e.) 3' AAA-TAA 5' - Correct Answers --E: 3' AAA-TAA 5'
mRNA in eukaryotes - Correct Answers -It is produced in the nucleus, contains
untranslated sequences and is translated in the cytoplasm
What determines the tertiary structure of proteins? - Correct Answers -Genes determine
the amino acid sequence of the protein, which determines its tertiary structure
Which of the following mutations is the most likely to be deleterious?
-a.) A switch mutation that leads to increased fertility in females
-b.) A missense mutation that enhances the function of a protein
-c.) A frameshift mutation in an essential gene
