MMG 301 Exam 3 With Complete
Solution
When squids that contain luminescent bacterial symbionts hatch, they do NOT contain a
bacterial symbiont. Symbiont transmission in this symbiosis is - Answer horizontal and
involves specific selection of the symbiont from the environment.
Aliivibrio fischeri symbionts benefit the Hawaiian bobtail squid by - Answer mimicking
the light of the moon, which helps the squid avoid nocturnal predators
Termites are capable of digesting cellulose and hemicellulose due to the presence of
__________. - Answer symbiotic bacteria in their gut.
Aphids that feed on carbohydrate-rich but nutrient-poor foods obtain ________ from their
endosymbiotic bacterial partners. - Answer amino acids.
Bacterial fermenters themselves are a significant source of nutrition for ruminants, but
not for hindgut fermenters, because __________. - Answer they pass through an acidic
chamber and are digested
The human microbiome contains all - Answer organisms present in and on the body.
Obligate anaerobes are likely to be found in the __________. - Answer colon
Symbionts can be acquired by an individual host organism horizontally (from the
environment) or vertically (from a parent). In humans, there is evidence that infants are
largely colonized by their parents' microbes, and family members living in the same
household have microbiomes that are more similar than those of individuals living
nearby. However, no two humans have identical microbiota, and certain factors, such
as diet and antibiotics, can alter the microbiome. This indicates that humans may be
colonized by __________. - Answer both vertical and horizontal transmission
All microorganisms that live in the human body are harmful. - Answer False.
All of the following are Gram-positive genera typically found on the skin EXCEPT
__________. - Answer Bacteroides
When a child begins to get its first teeth, what happens to the microbiota in the oral
cavity? - Answer The teeth are rapidly colonized by anaerobes, in particular
Streptococcus, that are specifically adapted to growth in biofilms on the surfaces of the
teeth.
Extensive microbial growth in a thick bacterial layer on the teeth is called - Answer
dental plaque.
Saliva contains relatively few microbes compared to other body sites, because
,__________. - Answer the concentration of antimicrobial enzymes limits their growth
The damaged areas of teeth caused by organic acids produced by dental plaque are
called - Answer dental caries
Which of these microorganisms is most likely to be found in the human stomach? -
Answer Helicobacter pylori
The human gastrointestinal tract includes all of the following EXCEPT the - Answer
epiglottis.
The most heavily colonized human organ by bacteria is the ________, containing
10111012 bacterial cells per gram. - Answer large intestine
The ability of humans to resist a disease is called - Answer immunity.
The bodys non-inducible, preexisting ability to recognize and destroy a variety of
pathogens or their products is called - Answer innate immunity.
Pattern recognition receptors are most directly used - Answer by phagocytes to detect
pathogens.
The primary function of a phagocyte is to - Answer both engulf and destroy pathogens.
The unique antigen-reactive proteins of T cells are - Answer T cell receptors.
MHC I proteins are found - Answer on all nucleated cells.
Adaptive immune responses are directed at pathogen molecules called - Answer
antigens.
Which of the following presents processed antigens to T cells? - Answer major
histocompatibility complex proteins
Which is an example of acquisition of natural passive immunity? - Answer a fetus
protected from disease by its mothers antibodies
The antigen-binding site of an antibody accommodates a small portion of the antigen
called a(n) - Answer epitope.
Which of these is often used as a prophylactic measure to protect a person against
future attack by a pathogen? - Answer vaccination.
Which of the following is an example of humoral immunity? - Answer the production of
antibodies by B cells
An attenuated strain of a pathogen - Answer has lost its virulence, but may be used to
create a vaccine.
Which type of vaccine could possibly cause a person to develop the disease? - Answer
Attenuated live vaccine.
, What is the hallmark of a conjugated vaccine? - Answer These vaccines contain weakly
antigenic elements plus a more potent antigenic protein.
The influenza vaccine is an example of a(n) - Answer inactivated killed vaccine.
What is the function of boosters? - Answer Boosters are injections that are given
periodically to maintain immunity.
The Hepatitis B vaccine is which type of vaccine? - Answer Subunit vaccine.
Which of the following can be used in creating a vaccine? - Answer attenuated bacteria,
inactivated viruses, or recombinant proteins
What is the drawback of live attenuated vaccines? - Answer They can cause disease in
some immunocompromised individuals.
The ability to cause disease is __________. - Answer pathogenicity
Certain traits that allow pathogens to create infection and cause disease are termed -
Answer virulence factors
Which of the following enzymes breaks down the "glue" that holds cells together? -
Answer Hyaluronidase.
Which of the following virulence factors would be found in Staphylococcus aureus? -
Answer Staphylokinase
How do fibrinolysins enhance a pathogen's virulence? - Answer They break down fibrin
proteins that are involved in clot formation, allowing the cells to penetrate deep into
damaged skin.
A pathogen must __________ in order for it to cause disease. - Answer attach and
multiply
Which of the following is most likely to cause disease? - Answer injection of 105 cells of
a highly virulent bacterial species into a mouse
How are immune cells able to detect foreign pathogens? - Answer They are able to
detect structures on the surfaces of foreign cells that are not found in the host.
How does a capsule help certain bacteria evade detection by the immune system? -
Answer The capsule is composed of polysaccharides that are similar to those found in
the host; thus, the immune system does not recognize it as foreign.
Which of the following microorganisms actually grows inside the macrophage? - Answer
Tuberculosis bacterium
How does the protozoan Trypanosoma evade detection by the immune system? -
Answer It can change the surface antigens frequently, preventing the immune system
from tracking it.
Solution
When squids that contain luminescent bacterial symbionts hatch, they do NOT contain a
bacterial symbiont. Symbiont transmission in this symbiosis is - Answer horizontal and
involves specific selection of the symbiont from the environment.
Aliivibrio fischeri symbionts benefit the Hawaiian bobtail squid by - Answer mimicking
the light of the moon, which helps the squid avoid nocturnal predators
Termites are capable of digesting cellulose and hemicellulose due to the presence of
__________. - Answer symbiotic bacteria in their gut.
Aphids that feed on carbohydrate-rich but nutrient-poor foods obtain ________ from their
endosymbiotic bacterial partners. - Answer amino acids.
Bacterial fermenters themselves are a significant source of nutrition for ruminants, but
not for hindgut fermenters, because __________. - Answer they pass through an acidic
chamber and are digested
The human microbiome contains all - Answer organisms present in and on the body.
Obligate anaerobes are likely to be found in the __________. - Answer colon
Symbionts can be acquired by an individual host organism horizontally (from the
environment) or vertically (from a parent). In humans, there is evidence that infants are
largely colonized by their parents' microbes, and family members living in the same
household have microbiomes that are more similar than those of individuals living
nearby. However, no two humans have identical microbiota, and certain factors, such
as diet and antibiotics, can alter the microbiome. This indicates that humans may be
colonized by __________. - Answer both vertical and horizontal transmission
All microorganisms that live in the human body are harmful. - Answer False.
All of the following are Gram-positive genera typically found on the skin EXCEPT
__________. - Answer Bacteroides
When a child begins to get its first teeth, what happens to the microbiota in the oral
cavity? - Answer The teeth are rapidly colonized by anaerobes, in particular
Streptococcus, that are specifically adapted to growth in biofilms on the surfaces of the
teeth.
Extensive microbial growth in a thick bacterial layer on the teeth is called - Answer
dental plaque.
Saliva contains relatively few microbes compared to other body sites, because
,__________. - Answer the concentration of antimicrobial enzymes limits their growth
The damaged areas of teeth caused by organic acids produced by dental plaque are
called - Answer dental caries
Which of these microorganisms is most likely to be found in the human stomach? -
Answer Helicobacter pylori
The human gastrointestinal tract includes all of the following EXCEPT the - Answer
epiglottis.
The most heavily colonized human organ by bacteria is the ________, containing
10111012 bacterial cells per gram. - Answer large intestine
The ability of humans to resist a disease is called - Answer immunity.
The bodys non-inducible, preexisting ability to recognize and destroy a variety of
pathogens or their products is called - Answer innate immunity.
Pattern recognition receptors are most directly used - Answer by phagocytes to detect
pathogens.
The primary function of a phagocyte is to - Answer both engulf and destroy pathogens.
The unique antigen-reactive proteins of T cells are - Answer T cell receptors.
MHC I proteins are found - Answer on all nucleated cells.
Adaptive immune responses are directed at pathogen molecules called - Answer
antigens.
Which of the following presents processed antigens to T cells? - Answer major
histocompatibility complex proteins
Which is an example of acquisition of natural passive immunity? - Answer a fetus
protected from disease by its mothers antibodies
The antigen-binding site of an antibody accommodates a small portion of the antigen
called a(n) - Answer epitope.
Which of these is often used as a prophylactic measure to protect a person against
future attack by a pathogen? - Answer vaccination.
Which of the following is an example of humoral immunity? - Answer the production of
antibodies by B cells
An attenuated strain of a pathogen - Answer has lost its virulence, but may be used to
create a vaccine.
Which type of vaccine could possibly cause a person to develop the disease? - Answer
Attenuated live vaccine.
, What is the hallmark of a conjugated vaccine? - Answer These vaccines contain weakly
antigenic elements plus a more potent antigenic protein.
The influenza vaccine is an example of a(n) - Answer inactivated killed vaccine.
What is the function of boosters? - Answer Boosters are injections that are given
periodically to maintain immunity.
The Hepatitis B vaccine is which type of vaccine? - Answer Subunit vaccine.
Which of the following can be used in creating a vaccine? - Answer attenuated bacteria,
inactivated viruses, or recombinant proteins
What is the drawback of live attenuated vaccines? - Answer They can cause disease in
some immunocompromised individuals.
The ability to cause disease is __________. - Answer pathogenicity
Certain traits that allow pathogens to create infection and cause disease are termed -
Answer virulence factors
Which of the following enzymes breaks down the "glue" that holds cells together? -
Answer Hyaluronidase.
Which of the following virulence factors would be found in Staphylococcus aureus? -
Answer Staphylokinase
How do fibrinolysins enhance a pathogen's virulence? - Answer They break down fibrin
proteins that are involved in clot formation, allowing the cells to penetrate deep into
damaged skin.
A pathogen must __________ in order for it to cause disease. - Answer attach and
multiply
Which of the following is most likely to cause disease? - Answer injection of 105 cells of
a highly virulent bacterial species into a mouse
How are immune cells able to detect foreign pathogens? - Answer They are able to
detect structures on the surfaces of foreign cells that are not found in the host.
How does a capsule help certain bacteria evade detection by the immune system? -
Answer The capsule is composed of polysaccharides that are similar to those found in
the host; thus, the immune system does not recognize it as foreign.
Which of the following microorganisms actually grows inside the macrophage? - Answer
Tuberculosis bacterium
How does the protozoan Trypanosoma evade detection by the immune system? -
Answer It can change the surface antigens frequently, preventing the immune system
from tracking it.
