Test 4 Questions Flashcards
Describe how the tetanus toxin produces deadly symptoms in humans. Be sure to include cell types, proteins, and processes involved.
The toxin binds to inhibitory neurons and blocks release of Glycine. The neurons constantly release acetylcholine, causing constant muscle contractions, eventually preventing breathing.
Describe the steps that must happen for a vaccines to produce life-long immunity to a pathogen. Be sure to include types, proteins, and processes involved.
A B cell must recognize an antigen on the vaccine. The B cell must interact with a TH2 cell that also recognizes the antigen. The B cell must produce effective antibodies against the antigen. The B cell must produce Memory cells.
A large number of new infections of a particular disease in one country within a limited time period is called a:
Epidemic
A major factor in the ability of Streptococcus species to cause disease is the ability to produce a:
capsule
A toxin that works only in the intestinal tract is called a:
Enterotoxin
A zoonosis is a disease that humans often acquire from a:
animal
The most abundant bacterial genus in the human skin microflora is:
Staphylococcus
The fact that the immune system does not recognize self-antigens is referred to as:
tolerance
The LD50 is the measure of the number of pathogen cells required to cause ___ in 50% of infected hosts
death
The cells that produce all of the circulating antibodies are____cells
plasma
Streptococcus species are common abundant members of the human microbiome in what part of the body?
Upper respiratory tract
A live non-virulent strain that serves as a vaccine is called a _____ strain.
attenuated
When phagocytes try to kill bacteria using oxygen radicals, it is referred to as a ____ burst
respiratory
A nonliving item that transmits a pathogen to a new host is called a:
fomite
The set of proteins that bind to antibody-tagged bacteria and cause lysis are called:
complement
The major antibody class produces during a primary immune response is:
IgM
TH2 cells recognize antigens presented by ___ cells
B
Cytokines are…
1)Proteins that insert in bacterial membranes leading to cell death
2)Antibodies that recognize virus-infected cells
3)Proteins that allow immune cells to recognize foreign antigens
4)Proteins that slow the growth of tumor cells
5)Proteins that stimulate the activity of immune cells
Proteins that stimulate the activity of immune cells
How does sugar aid in the process of tooth cavity development?
1)The sucrose can be broken down by fermentation
2)Creation of acid byproducts promotes enamel decay
3)Sucrose is used to produce a polysaccharide that allows for bacterial adherence to tooth surfaces
4)All of the above
5)None of the above
All of the above
In epidemiology, the value R0 refers to:
1)The average number of pathogen cells that must enter an host to cause an infection
2)The first person that exhibits an infection during an outbreak
3)The time period when no new infections are detected
4)The average number of additional individuals that will be infected by one infected host
The average number of additional individuals that will be infected by one infected host
An AB-form toxin is a toxin in which:
1)A single toxin protein must be cleaved into two parts in order to function
2)two proteins must be produced, one by the pathogen and one by the host, in order to have full effect
3)Two proteins act together, one binding the host cell and the other entering the cell
4)A toxin has different effects on two different host cell types
Two proteins act together, one binding the host cell and the other entering the cell
Which of the following are lymphocytes?
1)only B cells
2)only T cells
3)phagocytic cells
4)B and T cells
5)Phagocytic cells, B cells, and T cells
B and T cells
Macrophages are:
1)derived from bone marrow stem cells
2)part of the INNATE immune response
3)capable of presenting an antigen to a T cell
4)able to capture and destroy many pathogens they encounter
5)All of the above are TRUE statements
All of the above are TRUE statements
Memory cells allow rapid response to an antigen because:
1)They are present in high numbers
2)They do not require T cells for activation
3)They divide more rapidly than other cells
4)They are already filled with antibody molecules
They do not require T cells for activation
How is a macrophage protected from the oxygen and nitrogen radicals used for the destruction of pathogens?
1)The destruction takes place within a membrane-bound compartment
2)The macrophage contains many oxidases and nitrogenases that break down the radicals
3)Extra appendages separate the radicals from important organelles
4)The macrophage has a mucus barrier to keep pathogens away from its surface
The destruction takes place within a membrane-bound compartment
A disease that is “Endemic” is:
1)Spreading rapidly through a local population
2)Spreading rapidly through a very large area
3)Unable to be reduced by vaccination
4)caused by an unidentified pathogen
5)Constantly present at a low level within a population
Constantly present at a low level within a population
Which of the following factors alter vaginal microflora?
1)Fertility
2)Age
3)Hormone levels
4)pH
5)All of the above
All of the above
An example of a pattern recognition receptor (PRR) is:
1)Toll like receptors
2)B cell receptor
3)T cell receptor
4)Antibody
Toll like receptors
A disease that exhibits a high incidence in the USA during late summer and fall, and essentially no incidence during the winter, is indicative of:
1)A mosquito-borne disease
2)A direct host to host transferred disease
3)A disease transmitted by tree pollen
4)A disease transmitted in ground beef
A mosquito-borne disease
Which region of the human body is normally virtually devoid of bacteria?
1)Upper respiratory tract
2)Lower respiratory tract
3)Gastrointestinal tract
4)Sinuses
5)Hair follicles
Lower respiratory tract
Which of the following toxin names refers to the LPS in the Gram-negative outer membrane?
1)Exotoxin
2)α -toxin
3)Endotoxin
4)Protein toxin
5)Enterotoxin
Endotoxin
Which of the following is a likely cause of a Common Source Epidemic?
1)A mosquito transferring malaria to several individuals
2)A student with a cold sneezing on three professors
3)Contamination of food with Norovirus by an infected chef
4)An intravenous drug user with HIV passing a contaminated needle to another user
Contamination of food with Norovirus by an infected chef
Adherence to host cells can be increased by each of the following EXCEPT:
1)Surface proteins
2)Fimbriae
3)Pili
4)Capsules
5)Flagella
Flagella
A role of T cytotoxic cells in the immune response it to…
1)engulf pathogens
2)produce antibodies
3)directly kill pathogens
4)kill cells that are infected by a pathogen
5)increase the activity of macrophages
kill cells that are infected by a pathogen
The genus Bacteroids is very important in the human gut microflora because:
1)It frequently causes colitis
2) It breaks down complex polysaccharides
3)It produces many vitamins
4)It solubilizes fats
5)It spreads many antibiotic resistance genes
It breaks down complex polysaccharides
Which of the following types of proteins is not likely to be considered a virulence factor?
1)An exotoxin
2)A pilus subunit
3)A DNA Polymerase
4)A chelator
5)A fimbriae subunit
A DNA Polymerase
In the field of epidemiology, the term “reservoir” refers to:
1)A location where a pathogen can be maintained in order to allow future infection of a population
2)A stock of vaccine maintained to combat a disease outbreak
3)A stock of antibiotic maintained to combat a disease outbreak
4)A stock of pathogen stored in a safe place for future research
A location where a pathogen can be maintained in order to allow future infection of a population
VDJ recombination is required for:
1)Production of various types of phagocytes
2)Production of antibody diversity
3)Elimination of self reactive antibodies
4)Acquisition of antibiotic resistance
Production of antibody diversity
Gastric cancer can result from the prolonged infection by what genus of bacteria?
1)Bacteroids
2)Helicobacter
3)Escherichia
4)Clostridium
5)Methanobrevibacteria
Helicobacter
Class II Major Histocompatibility Complexes function as antigen-presenting molecules on:
1)The surface of all nucleated cells in the entire body
2)Macrophages, dendritic cells, and B lymphocytes
3)Red blood cells
4) 1 and 2
Macrophages, dendritic cells, and B lymphocytes
The toxin produces by clostridium botulinum causes what symptoms in humans?
1)Constant muscle contraction
2)Constant muscle relaxation
3)Diarrhea
4)Muscle cell lysis
5)Blood cell lysis
Constant muscle relaxation
Second exposure to antigens primarily triggers the production of:
1)IgA
2)IgD
3)IgE
4)IgG
IgG
What type of nutrient is frequently a limiting factor in the growth of microorganisms within a host?
1)Iron
2)Lipids
3)Magnesium
4)Proteins
5)Sugars
Iron
A host to host epidemic generally exhibits what pattern of incidence in a population?
1)A rapid increase followed by a rapid decline
2)A rapid increase followed by a very slow decline
3)A slow increase followed by a rapid decline
4)A slow increase followed by a slow decline
A slow increase followed by a slow decline
Which of the following does NOT increase the ability of phagocytes to engulf bacteria?
1)Lipopolysaccharide on the bacterial surface
2)Cytokine activation by T-cells
3)Capsule on the bacterial surface
4)Peptidoglycan on the bacterial surface
5)Opsonization of the bacterial surface
Capsule on the bacterial surface
As you move from the stomach further down the gastrointestinal tract, how do pH and oxygen availability change?
1)pH and oxygen availability increase
2)pH and oxygen availability decrease
3)pH increases and oxygen availability decreases
4)pH decreases and oxygen availability increases
5)pH and oxygen availability remain constant throughout
pH increases and oxygen availability decreases
The term “Opsonization” refers to:
1)Specific interaction between a normal microbial flora species and a host cell surface
2)Attachment of a viral particle to a host cell surface
3)Removal of the viral capsid from the nucleic acid following cell entry
4)Binding of an antibody to a pathogen leading to increased phagocytosis
5)Recognition of a pathogen PAMP by a phagocyte
Binding of an antibody to a pathogen leading to increased phagocytosis
