BIO 148 EXAM 2 PRACTICE TEST QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE
2025/2026
. 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?
a. No, because the cells of the eye have different genes than the cells of the cheek.
b. No, because the cells of the eye have different chromosomes than the cells of the cheek.
c. Yes, because both cells have the same genes
d. Yes, because both cells express the same genes - Answers C
2. RNA polymerase......
a. Starts transcribing at the first intron
b. Starts transcribing at the start codon
c. Transcribes the coding strand 5' to 3'
d. Synthesizes a nucleic acid that is complementary to the template strand
e. Answers (a), (c) and (d) are all correct - Answers D
For most multicellular organisms, how can the cells of a single organism have different shapes
and actions?
a. They express different genes
b. They have different gene switches (enhancers)
c. They have different genes
d. They have different chromosomes
e. Both a and b - Answers A
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?
, a. The lactase gene will be transcribed but the mRNA will not be translated
b. The lactase gene will be transcribed but the RNA will not be processed
c. The lactase gene will not be transcribed so the mRNA will not be translated
d. The lactase gene will be translated but the mRNA will not be transcribed - Answers C
Within the eukaryotic cell, transcription occurs in the __________ and RNA splicing occurs in the
_____.
a. Nucleus; nucleus
b. Cytoplasm; nucleus
c. Cytoplasm; cytoplasm
d. Nucleus; cytoplasm - Answers A
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. - Answers A
Which of the following is a part of a DNA molecule?
a. Promoter e. A and C only
b. Switch
c. Gene
d. All of the above - Answers D
Use the diagram above to answer the next two questions.
8. Transcription will occur from right to left in the diagram above. Which DNA strand is the
coding strand?
a. X
b. Z
2025/2026
. 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?
a. No, because the cells of the eye have different genes than the cells of the cheek.
b. No, because the cells of the eye have different chromosomes than the cells of the cheek.
c. Yes, because both cells have the same genes
d. Yes, because both cells express the same genes - Answers C
2. RNA polymerase......
a. Starts transcribing at the first intron
b. Starts transcribing at the start codon
c. Transcribes the coding strand 5' to 3'
d. Synthesizes a nucleic acid that is complementary to the template strand
e. Answers (a), (c) and (d) are all correct - Answers D
For most multicellular organisms, how can the cells of a single organism have different shapes
and actions?
a. They express different genes
b. They have different gene switches (enhancers)
c. They have different genes
d. They have different chromosomes
e. Both a and b - Answers A
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?
, a. The lactase gene will be transcribed but the mRNA will not be translated
b. The lactase gene will be transcribed but the RNA will not be processed
c. The lactase gene will not be transcribed so the mRNA will not be translated
d. The lactase gene will be translated but the mRNA will not be transcribed - Answers C
Within the eukaryotic cell, transcription occurs in the __________ and RNA splicing occurs in the
_____.
a. Nucleus; nucleus
b. Cytoplasm; nucleus
c. Cytoplasm; cytoplasm
d. Nucleus; cytoplasm - Answers A
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. - Answers A
Which of the following is a part of a DNA molecule?
a. Promoter e. A and C only
b. Switch
c. Gene
d. All of the above - Answers D
Use the diagram above to answer the next two questions.
8. Transcription will occur from right to left in the diagram above. Which DNA strand is the
coding strand?
a. X
b. Z
