©EMILLECT2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Biology Ch 15 Fifth Edition Brooker BRCC
1033 Exam Practice Questions and
Answers
Figure 15.1 A missense mutation that causes red blood cells to sickle in sickle cell disease. Scanning
electron micrographs of (a) a normal red blood cell and (b) a sickled red blood cell. As shown above the
micrographs, a missense mutation in the β-globin gene (which codes for a subunit of hemoglobin)
changes the sixth amino acid in the β-globin polypeptide from glutamic acid (Glu) to valine (Val). (c) This
micrograph shows how this alteration to the structure of β-globin causes the formation of abnormal
fiber-like structures. In normal red blood cells, hemoglobin proteins do not form fibers.
Concept Check: Based on the fiber-like structures seen in part (c) of this figure, what aspect of
hemoglobin structure does a glutamic acid at the sixth
position in normal β-globin prevent? Speculate as to how the charge of this amino acid may play a role. -
ANSWER✔✔-Chapter 15 Concept Checks
Page 1/16
, ©EMILLECT2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Figure 15.1 At neutral pH, glutamic acid is negatively charged. Perhaps the negative
charges repel each other and prevent hemoglobin proteins from aggregating into
fiber-like structures
Figure 15.3 Example of a somatic mutation. This child has a streak of white hair. This is due to a somatic
mutation in a single cell during embryonic development. This cell continued to divide to produce a streak
of white hair.
Concept Check: Can this child with a streak of white hair transmit this
trait to his future offspring? - ANSWER✔✔-Chapter 15 Concept Checks
Figure 15.3 This trait is due to a mutation that occurred in a somatic cell, so it cannot be transmitted to
the individual's offspring.
Figure 15.6 Formation and structure of a thymine dimer.
Concept Check: Why is a thymine dimer harmful? - ANSWER✔✔-Chapter 15 Concept Checks
Page 2/16
, ©EMILLECT2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Figure 15.6 A thymine dimer is harmful because it can cause an error in DNA replication that results in a
mutation.
Figure 15.8 Nucleotide excision repair in E. coli.
Concept Check: Which components of the NER system are responsible for removing the damaged DNA? -
ANSWER✔✔-Chapter 15 Concept Checks
Figure 15.8 UvrC and UvrD are responsible for removing the damaged DNA. UvrC
makes cuts on both sides of the damage, and then UvrD removes the damaged region.
Figure 15.9 An individual affected by xeroderma pigmentosum.
Concept Check: Why is this person so sensitive to sunlight? - ANSWER✔✔-Chapter 15 Concept Checks
Page 3/16
FIRST PUBLISH OCTOBER 2024
Biology Ch 15 Fifth Edition Brooker BRCC
1033 Exam Practice Questions and
Answers
Figure 15.1 A missense mutation that causes red blood cells to sickle in sickle cell disease. Scanning
electron micrographs of (a) a normal red blood cell and (b) a sickled red blood cell. As shown above the
micrographs, a missense mutation in the β-globin gene (which codes for a subunit of hemoglobin)
changes the sixth amino acid in the β-globin polypeptide from glutamic acid (Glu) to valine (Val). (c) This
micrograph shows how this alteration to the structure of β-globin causes the formation of abnormal
fiber-like structures. In normal red blood cells, hemoglobin proteins do not form fibers.
Concept Check: Based on the fiber-like structures seen in part (c) of this figure, what aspect of
hemoglobin structure does a glutamic acid at the sixth
position in normal β-globin prevent? Speculate as to how the charge of this amino acid may play a role. -
ANSWER✔✔-Chapter 15 Concept Checks
Page 1/16
, ©EMILLECT2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Figure 15.1 At neutral pH, glutamic acid is negatively charged. Perhaps the negative
charges repel each other and prevent hemoglobin proteins from aggregating into
fiber-like structures
Figure 15.3 Example of a somatic mutation. This child has a streak of white hair. This is due to a somatic
mutation in a single cell during embryonic development. This cell continued to divide to produce a streak
of white hair.
Concept Check: Can this child with a streak of white hair transmit this
trait to his future offspring? - ANSWER✔✔-Chapter 15 Concept Checks
Figure 15.3 This trait is due to a mutation that occurred in a somatic cell, so it cannot be transmitted to
the individual's offspring.
Figure 15.6 Formation and structure of a thymine dimer.
Concept Check: Why is a thymine dimer harmful? - ANSWER✔✔-Chapter 15 Concept Checks
Page 2/16
, ©EMILLECT2024/2025 ACADEMIC YEAR. ALL RIGHTS RESERVED
FIRST PUBLISH OCTOBER 2024
Figure 15.6 A thymine dimer is harmful because it can cause an error in DNA replication that results in a
mutation.
Figure 15.8 Nucleotide excision repair in E. coli.
Concept Check: Which components of the NER system are responsible for removing the damaged DNA? -
ANSWER✔✔-Chapter 15 Concept Checks
Figure 15.8 UvrC and UvrD are responsible for removing the damaged DNA. UvrC
makes cuts on both sides of the damage, and then UvrD removes the damaged region.
Figure 15.9 An individual affected by xeroderma pigmentosum.
Concept Check: Why is this person so sensitive to sunlight? - ANSWER✔✔-Chapter 15 Concept Checks
Page 3/16
