JANEWAY'S IMMUNOBIOLOGY, 9TH EDITION
INNATE IMMUNITY: THE FIRST LINES OF DEFENSE
Anatomic barriers and initial chemical defenses
2-1 Infectious diseases are caused by diverse living agents that replicate in their hosts
2.1 Multiple choice: Antibodies, complement proteins, and phagocytic cells provide effective
protection against all of the following types of infections in Figure Q2.1, except:
Figure Q2.1
2.2 Multiple choice: Pathogenic infections induce damage to the host by a variety of
mechanisms. While many mechanisms are direct effects of the pathogen, some
damaging mechanisms result from the immune response to the infection, as illustrated in
Figure Q2.2. Examples of damage caused by the host immune response are:
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, Figure Q2.2
2.3 True/False: Mucosal surfaces and external epithelia are major routes of pathogenic
infection. Mucosal surfaces are found in tissues such as the gastrointestinal tract, the
reproductive tract and the mouth and respiratory tract. While the mouth and respiratory
tract are routes of virus but not bacterial infections, the gastrointestinal tract is the route
for bacterial but not virus infections.
2-2 Epithelial surfaces of the body provide the first barrier against infection
2.4 Multiple choice: Epithelial surfaces provide the first line of defense against infection by
the use of several types of mechanisms. One of the chemical mechanisms used by
epithelia is:
A. Joining of epithelial cells by tight junctions
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, B. Secretion of antimicrobial peptides by epithelial cells
C. Production of mucus, tears, or saliva in the nose, eyes, and oral cavity
D. Movement of mucus by cilia
E. Peristalsis in the gastrointestinal tract
2.5 Multiple choice: Women with urinary tract infections caused by E. coli are generally
treated with a course of antibiotics. A common complication of the antibiotic treatment is
the occurrence of a vaginal yeast infection caused by Candida albicans, an organism
that is normally present in very low numbers in the human vaginal tract. This
complication occurs because:
A. The E. coli infection damages the reproductive epithelium, causing a breach in the
tight junctions and allowing invasion by the Candida albicans.
B. The E. coli infection induces adhesion molecule expression on the reproductive
epithelium, allowing attachment of the yeast.
C. The antibiotic treatment kills all strains of fungi present in the reproductive tract,
except the Candida albicans.
D. The E. coli infection causes gastrointestinal distress leading to diarrhea.
E. The antibiotics kill many of the commensal organisms in the reproductive tract,
allowing overgrowth of the fungus.
2-3 Infectious agents must overcome innate host defenses to establish a focus of
infection
2.6 Short answer: Our environment contains masses of microorganisms, many of which
reside as commensal organisms on our body’s mucosal and epithelial surfaces without
causing disease. What two features distinguish a pathogenic microbe from these
commensal microbes?
2-4 Epithelial cells and phagocytes produce several kinds of antimicrobial proteins
2.7 Multiple choice: Streptococcus pneumoniae is a Gram-positive bacterium that colonizes
the mucosal surface of the upper respiratory tract in humans. The presence of this
bacterium in the nose and throat is widespread in the population, and in most people,
colonization with Strep. pneumoniae is asymptomatic. Figure Q2.7 shows a comparison
of in vitro growth curves of the wild-type strain of Strep. pneumoniae, as well as a Strep.
pneumoniae mutant strain with a defect in one bacterial gene. The graph on the right
shows the growth curve following addition of lysozyme during the logarithmic phase of
bacterial growth.
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INNATE IMMUNITY: THE FIRST LINES OF DEFENSE
Anatomic barriers and initial chemical defenses
2-1 Infectious diseases are caused by diverse living agents that replicate in their hosts
2.1 Multiple choice: Antibodies, complement proteins, and phagocytic cells provide effective
protection against all of the following types of infections in Figure Q2.1, except:
Figure Q2.1
2.2 Multiple choice: Pathogenic infections induce damage to the host by a variety of
mechanisms. While many mechanisms are direct effects of the pathogen, some
damaging mechanisms result from the immune response to the infection, as illustrated in
Figure Q2.2. Examples of damage caused by the host immune response are:
Page 1 of 20
, Figure Q2.2
2.3 True/False: Mucosal surfaces and external epithelia are major routes of pathogenic
infection. Mucosal surfaces are found in tissues such as the gastrointestinal tract, the
reproductive tract and the mouth and respiratory tract. While the mouth and respiratory
tract are routes of virus but not bacterial infections, the gastrointestinal tract is the route
for bacterial but not virus infections.
2-2 Epithelial surfaces of the body provide the first barrier against infection
2.4 Multiple choice: Epithelial surfaces provide the first line of defense against infection by
the use of several types of mechanisms. One of the chemical mechanisms used by
epithelia is:
A. Joining of epithelial cells by tight junctions
Page 2 of 20
, B. Secretion of antimicrobial peptides by epithelial cells
C. Production of mucus, tears, or saliva in the nose, eyes, and oral cavity
D. Movement of mucus by cilia
E. Peristalsis in the gastrointestinal tract
2.5 Multiple choice: Women with urinary tract infections caused by E. coli are generally
treated with a course of antibiotics. A common complication of the antibiotic treatment is
the occurrence of a vaginal yeast infection caused by Candida albicans, an organism
that is normally present in very low numbers in the human vaginal tract. This
complication occurs because:
A. The E. coli infection damages the reproductive epithelium, causing a breach in the
tight junctions and allowing invasion by the Candida albicans.
B. The E. coli infection induces adhesion molecule expression on the reproductive
epithelium, allowing attachment of the yeast.
C. The antibiotic treatment kills all strains of fungi present in the reproductive tract,
except the Candida albicans.
D. The E. coli infection causes gastrointestinal distress leading to diarrhea.
E. The antibiotics kill many of the commensal organisms in the reproductive tract,
allowing overgrowth of the fungus.
2-3 Infectious agents must overcome innate host defenses to establish a focus of
infection
2.6 Short answer: Our environment contains masses of microorganisms, many of which
reside as commensal organisms on our body’s mucosal and epithelial surfaces without
causing disease. What two features distinguish a pathogenic microbe from these
commensal microbes?
2-4 Epithelial cells and phagocytes produce several kinds of antimicrobial proteins
2.7 Multiple choice: Streptococcus pneumoniae is a Gram-positive bacterium that colonizes
the mucosal surface of the upper respiratory tract in humans. The presence of this
bacterium in the nose and throat is widespread in the population, and in most people,
colonization with Strep. pneumoniae is asymptomatic. Figure Q2.7 shows a comparison
of in vitro growth curves of the wild-type strain of Strep. pneumoniae, as well as a Strep.
pneumoniae mutant strain with a defect in one bacterial gene. The graph on the right
shows the growth curve following addition of lysozyme during the logarithmic phase of
bacterial growth.
Page 3 of 20
