Med Microbiology Chapter 15, 16, 17
Define: Coagulase
A bacterial enzyme that causes blood plasma to clot
Define: Aflatoxin
A carcinogenic toxin produced by aspergillus flavus
What is a plasma cell?
A cell that produces antibodies
Define: Genotoxin
A chemical that damages DNA or RNA
Define: Lipid A
A component of the gram-negative outer membrane; endotoxin
Define: Intoxication
A condition resulting from the ingestion of a microbially produced toxin
Define: Inclusion Body
A granule or viral particle in the cytoplasm or nucleus of some infected cells, important in the identification of viruses that causes infection
Define: Streptolysin
A hemolytic enzyme, produced by streptococci
Define: Agranulocyte
A leukocyte without visible granules in the cytoplasm when viewed though a light microscope; includes monocytes and lymphocytes
Define: Abscess
A localized accumulation of pus
Define: Biofilm
A microbial community that usually forms as a slimy layer on a surface
Which of these effects is most likely to occur if a pathogen enters the body by a portal of entry other than the preferred one
A milder disease will result
Define: Syncytium
A multinucleated mass produced by fusion of multiple individual cells
Define: Saxitoxin
A neurotoxin produced by some dinoflagellates
Define: Phalloidin
A peptide toxin produced by Amanita phalloides, affects plasma membrane function
Define: Amanitin
A polypeptide toxin produced by amanita spp. inhibits RNA polymerase
Define: Parenteral Route
A portal of entry for pathogens by deposition directly into tissues beneath the skin and mucous membranes
Define: Exotoxin
A protein toxin released from living, mostly gram-positive bacterial cells
Define: Antitoxin
A specific antibody produced by the body in response to a bacterial exotoxin or its toxoid
Define: Septic Shock
A sudden drop in blood pressure induced by bacterial toxins
Define: Invasin
A surface protein produced by Salmonella Typhimurium and Escherichia coli that rearranges nearby actin filaments in the cytoskeleton of a host cell
Define: Mycotoxin
A toxic substance produced by a fungus
Define: Ergot
A toxin produced in sclerotia by the fungus Claviceps purpurea that causes ergotism
Which of the following is an INCORRECT statement about antimicrobial peptides (AMPs)?
AMPs have a narrow spectrum of antimicrobial activities.
Which of the following statements about T-dependent antigens is true?
Activation of a B cell by a T-dependent antigen requires cytokines secreted by a TH cell.
The resistance to reinfection with measles virus following recovery from measles infection is called __________.
Adaptive Immunity
Dr. Trapper wasn't going to give up easily and continued to scan the overall field for bacterial clues, but all he found were more immune cells. Soon, he noticed something else interesting...several cells were interacting! The likely identities of these cells based on morphologies could be best described as:
Adaptive immune cell and an antigen presenting cell
Which of these substances are most important in the establishment of biofilms
Adhesins
__________ are molecules on bacterial cell surfaces that enable them to adhere to the surface of host cells.
Adhesins
Which of the following antibody functions work to enhance microbe phagocytosis?
Agglutination and opsonization
Which of the following is NOT a cytopathic effect (CPE) of viruses? the formation of a syncytium chromosomal changes in the host cell formation of inclusion bodies
All of the listed choices are possible cytopathic effects of viruses.
Types of Macrophages: Lungs
Alveolar macrophages
Define: Antimicrobial Peptide (AMP)
An antibiotic that is bactericidal and has a broad spectrum of activity; see bacteriocin
Define: Superantigen
An antigen that activates many different T cells, thereby eliciting a large immune response
Define: Receptor
An attachment for a pathogen on a host cell
Define: Hyaluronidase
An enzyme secreted by certain bacteria that hydrolyses hyaluronic acid and helps spread microorganisms form their initial site of infection
Define: collagenase
An enzyme that hydrolyzes collagen
Define: Hemolysin
An enzyme that lyses red blood cells
Define: Kinase
An enzyme that removes a from ATP and attaches it to another molecule. A bacterial enzyme that breaks down fibrin (blood clots)
Define: Toxoid
An inactivated toxin
Which of the following would be an example of an infection initiated via the parenteral route?
An individual contracts hepatitis B from an accidental stick with a contaminated needle.
If this particular antigen attempts to re-infect Caleb, it's in for a bigger fight. By getting activation of adaptive immune cells such as B-cells and T-cells, the body generates an extra layer of protection. What is a critical advantage for Caleb the next time he encounters this antigen?
Anamnestic (memory) responses and future vaccinations to augment the response
Which of these molecules or structures is/are NOT associated with innate immunity?
Antibodies
Which of these statements is NOT true of antibody molecules?
Antibody molecules can directly destroy antigens.
Define: Shock
Any life-threatening loss of blood pressure. See also septic Shock
Define: Toxin
Any poisonous substance produced by a microorganism
Define: Neutrophils
Are the most abundant type of white blood cells, circulate in the blood & enter tissues @ sites of infection (60-70%)
Define: Adherence
Attachment of a microbe or phagocyte to another's plasma membrane or another surface
Define: Kinins
Attract neutrophils to injured area
Which domain of the A-B toxin binds to cell surface receptors on the host cell?
B Domain
Define: Siderophore
Bacterial iron-binding proteins
The scum that builds up on shower doors, the formation of dental plaque on teeth, and the algae growth on the walls of swimming pools are all examples of __________.
Biofilms
Which of these pathogens would most likely be attacked by antibody-dependent cell-mediated cytotoxicity?
Blood Flukes (Schistosomes)
Caleb recovered without incident, but because there are millions of cases of ear infections every year in the U.S., Dr. Trapper wanted to make sure that this would not be the first of many recurrent ear infections for his son. He wanted to ensure that Caleb did not have an underlying immunodeficiency that would cause his future responses to fight antigens suboptimally. He asked the physician to do a serology analysis of Caleb, which consisted of probing for each antibody isotype found and to report how much is present. The analysis yielded the following results. What might you conclude from this? ProbeQualitative Result Anti-whole human antiserum+++ Anti-IgG++ Anti-IgA++ Anti-IgM+
Caleb has a normal response
How can capsules enable bacteria to evade the immune system?
Capsules block the complement biding sites on the surface of the pathogen.
Which of the following can release histamines?
Cells from damaged tissues and the complement pathway
Which of the following statements concerning cellular immunity is FALSE?
Cellular immunity involves cells that recognize antigens and make specific antibodies against them.
Define: Antigenic Variation
Changes in surface antigens that occur in a microbial population
A new chemical messenger has been discovered that enhances the chemotaxis of macrophages and neutrophils toward sites of infection. It would be specifically classified as a(n) __________.
Chemokine
Which of the following is a true statement about the major histocompatibility complex (MHC)?
Class I MHC are found on the plasma membranes of mammalian nucleated cells. Class II MHC molecules exist only on the surface of antigen-presenting molecules (APCs). Thymic selection will rid the body of T cells that will not recognize MHC molecules of the host. The MHC is a collection of genes that encode molecules of genetically diverse glycoproteins.
Antigenic stimulation of a particular B cell that results in the production of a large number of plasma and memory cells, all capable of responding to that antigen, is referred to as __________.
Clonal Selection
Which term best describes the symbiotic relationship between humans and most of the normal microbiota that live on our human skin?
Commensalism
The ID50 for cutaneous anthrax due to Bacillus anthracis is 10 to 50 endospores, while the ID50 for inhalation anthrax is 10,000 to 20,000 endospores. This means that __________.
Cutaneous anthrax is easier to acquire than inhalation anthrax
Given the following LD50 values for Bacillus anthracis, through which portal of entry is it easiest to get anthrax
Cutaneous: 50 endospores
Which type of cell directly attacks infected cells?
Cytotoxic T-cells
HIV directly infects T-cells. Why is this problematic for cell-mediated immunity?
Cytotoxic T-cells begin to attack the virally infected T-cells, reducing the number of T-cells in the body.
An exotoxin that has the ability to kill or damage host cells is referred to as a(n)
Cytotoxin
According to the animation, on which day does the production of IgG occur in the secondary response?
Day Five
Classify portals of entry: Parenteral Route
Deep wounds, Surgery, injections
What makes agglutination by antibodies possible?
Each antibody has at least two antigen-binding sites.
Which of the following is the most likely possible diagnosis for Caleb?
Ear Infection
Which of the following toxins is NOT produced by a bacterium as a result of lysogenic conversion
Endotoxin
What are the initial signs and symptoms of fifth disease (Erythema infectiosum)?
Fever, runny nose, and headache
What cell structures does Neisseria gonorrhoeae use to attach and enter host epithelial cells
Fimbriae
According to the video, on what day does IgM first appear?
Five Days
Which of the following features of Salmonella prevent it from being phagocytosed
Flagella
Which of the following are possible locations for bacterial adhesins
Flagella, Pili, Fimbriae
Define: Urine
Flow and vaginal secretions move out m/o
View scenarios for the initiation of an infection and determine whether they relate to the number of invading microbes or adherence to the host tissue: Number of Invading Microbes
For cutaneous anthrax, the infectious dose is 10 to 50 endospores, whereas for inhalation anthrax, the infectious doses are 10,000 to 20,000 and 250,000 to 1,000,000 endospores, respectively. For Vibrio cholerae, the infectious does is 10^8 cells, but if stomach acid is neutralized with bicarbonate, this number decreases significantly
The most abundant Ig in the blood serum is __________. D,G,E,A,M
G
Classify portals of entry: Mucous Membrane
GI track, Conjunctivae, Respiratory track, genitourinary track
Chemical Factors of the GI track
Gastric juices, the stomach is made up of HCL, enzymes, and mucus pH1.2-3.0
Neutrophils, basophils, and eosinophils are collectively referred to as __________.
Granulocytes
Define: Leukotrienes
Help phagocytes to attach to pathogens
Immune cells that secrete cytokines and activate other immune cells are:
Helper T-cells
How do helper T-cells and cytotoxic T-cells work together?
Helper T-cells produce cytokines to activate other cells of the immune system.
Antibodies are a part of which type of immunity?
Humoral
Which part of the adaptive immune response involves B cells?
Humoral
Which of the following enzymes breaks down the "glue" that holds cells together?
Hyaluronidase
Saliva contains
IgA, urea and uric acid
Which of the following is a correct match?
IgA: found in secretions such as colostrum, tears, and mucus
Which of the following antibody classes play a role in allergic reactions?
IgE
Which of the following is the least abundant Ig?
IgE
Which of these processes is in the proper sequence?
IgE is formed; IgE binds to mast cells and basophils; antigen binds IgE; histamine is released.
If a patient has been exposed to an antigen for the first time, which class of immunoglobulin appears first?
IgM
In the primary immune response, the _____ antibody class is produced first, followed by production of the longer lasting _____ antibody class.
IgM, IgG
Which of these statements is NOT true for bacterial capsules
Immune system antibodies are not produced against a capsule
Define: Specific Resistance
Immunity
What is IL-1
Increases production of T cells
Which one of these is NOT an example of pathogen entry via the parenteral route
Infection of a hair follicle
Which of the following statements about innate immunity is true?
Innate immunity is present at birth
Where do Salmonella pathogens grow and replicate in the infected host?
Inside phagocytes
First Line of Defense
Intact skin, mucous membranes and their secretions, normal microbiota
Define: Prostaglandins
Intensify the action of histamine and kinins to help phagocytes move through the capillary walls
While we usually think of fever as a bad thing, a fever is actually signifying that an immune response is progressing! Overall, which of the following cytokines would be most involved in increasing Caleb's fever response?
Interleukin-1
Why is vasodilation important to tissue repair?
It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage.
How does the protozoan Trypanosoma evade detection by the immune system?
It can change the surface antigens frequently, preventing the immune system from tracking it.
Why is a release of endotoxin into the bloodstream potentially deadly?
It can lower blood pressure and cause the patient to go into shock.
Which of the following statements is NOT of the IgA antibody class?
It can trigger the complement cascade.
Which of the following statements concerning adaptive immunity is FALSE?
It is always present and instantly protects against infection.
Which of the following statements concerning lysozyme is FALSE?
It is an organelle in white blood cells.
Bacillus anthracis can cause infection via three different portals of entry. The ID50 of cutaneous anthrax is 10 to 50 endospores, whereas inhalation anthrax requires 10,000 to 20,000 endospores, and gastrointestinal anthrax requires 250,000 to 1,000,000 endospores. Which statement best describes a conclusion that can be drawn based on this information? Note: The portal of entry describes the route by which a pathogen gains access to the body. For pathogens that cause more than one type of infection, the infectious dose (ID50) is calculated based on each portal of entry. As a result, ID50 is not an absolute value, but rather, compares relative virulence under experimental conditions.
It is significantly easier to be infected with cutaneous anthrax as compared to other forms of anthrax The ID50 through the skin is only 10 to 50 endospores; thus, it is easier to acquire cutaneous anthrax than other forms of anthrax
Which of the following does NOT accurately describe innate immunity?
It produces strong, long-lasting memory responses.
The Epidermis is the outer layer of the skin, that contains what chemical
Keratin
Types of Macrophages: Liver
Kupffer's cells
Differential WBC count "decrease" # of leukocytes
Leukopenia - salmonellosis and some viral infections
Endotoxins are also known as
Lipid A
Which of these cells do NOT have phagocytic activity?
Lymphocytes
Which of the following is NOT an effect an antibody might have on a target cell?
Lysis
Where is the site of Shigella attachment in the host?
M cells
Define: Monocytes
Mature into macrophages
Which cells are involved in a secondary response?
Memory B cells and plasma cells
he adaptive immune response, or third line of defense, is activated when the first and second lines of defense do not succeed in containing an infection. It is adaptive because the cells in this part of the immune system are capable of responding to specific pathogens. Another important feature of the third line is the ability of these cells to create memory cells. Why are memory cells an important product of an immune response?
Memory cells allow subsequent immune responses against the same antigen to occur more strongly and more quickly.
The ID50 for many pathogens is significantly smaller when testing with gnotobiotic animals compared to animals with normal microbiota. This is likely because of __________.
Microbial antagonism
Types of Macrophages: Nervous System
Microglial cells
Define: Pathogen-Associated Molecular Patterns (PAMP)
Molecules present on pathogens and not self
What are leukocidins?
Molecules that are capable of destroying phagocytes
Define: lymphocytes
Natural killer cells T and B Cells
View scenarios for the initiation of an infection and determine whether they relate to the number of invading microbes or adherence to the host tissue: Adherence to the host tissue
Neisseria gonorrhoeae uses fimbriae to attach to cells in the genitourinary tract, eyes, and pharynx Staphylococcus aureus binds and infects skin by a mechanism that resembles viral attachment Treponema pallidum uses its tapered end as a hook to attach to host cells during a syphilis infection Enteropathogenic strains of Escherichia coli have fimbriae that bind to specific regions of the small intestine.
Meningitis and gonorrhea are caused by
Neisseria species.
A patient who has been hospitalized with uncontrolled muscle spasms has probably been infected with bacteria that secrete a(n)
Neurotoxin
Most patients would happily accept a prescription for antibiotics from the pediatrician and go home. But as a microbiologist, Dr. Trapper wanted to identify the infectious etiology and see what was going on inside his son. Even though it's not standard procedure for otitis media, he asked for some of the fluid contained behind the eardrum to be collected with a syringe (tympanocentesis) so he could analyze it for culture and sensitivity in his lab. He stained the fluid and examined it under the microscopic field. Interestingly, although he did not find any noticeable bacterial organisms, he did find high numbers of this characteristic responding cell type (picture), which could likely be identified as a:
Neutrophil
Which type of leukocyte is the most abundant in blood?
Neutrophils
Why would a body cell that is not a phagocyte need to present antigens?
Non-phagocytic body cells can become infected with a virus.
Hepatitis B virus transmitted by a finger-stick device enters the host via which portal of entry
Parental
Which are portals of entry and exit found within the human body?
Parenteral route, Skin, and Mucous membrane
Define: Endotoxin
Parts of a bacteria cell wall, released from dead bacteria
You get the following antibody titers against West Nile virus in three patients. Which patient probably has a current infection? Patient A: 128 IgG, 0 IgM Patient B: 128 IgG, 256 IgM Patient C: 0 IgG, 0 IgM
Patient B
Second Line of Defense
Phagocyte (WBC), inflammation, fever, and antimicrobial substance
What is the role of plasma cells in humoral immunity
Plasma cells produce antibodies.
Which disease is correctly matched with the common portal of entry
Poliomyelitis; mucous membranes of gastrointestinal tract
Define: Cytokines
Produced by macrophages
Define: Saliva
Produced by the Salivary glands
Define: Mucus
Produced by the epithelial cells in the GI and respiratory tracks (traps m/o) ciliary escalator
Define: Tears
Produced by the lacrimal glands
Which of the following is a reaction of the adaptive immune response?
Production of antibodies
How is phagocytosis in the immune system different from protozoan phagocytosis?
Protozoan phagocytosis is used for feeding; phagocytosis by immune cells is used to fight infection.
Define: Histamine
Release in response to injury
Which would be the most UNLIKELY location to find adhesin molecules on a newly discovered bacterium
Ribosomes
What is the etiologic agent of typhoid?
Salmonella
Define: Dendritic Cells
Samplers
Define: Ligand
See adhesin
When blood cells are removed from blood, the remaining liquid is referred to as __________.
Serum
Define: Acute-Phase Proteins
Serum proteins who concentration changes by at least 25% during inflammation
In mice, the LD50 for staphylococcal enterotoxin is 1350 ng/kg, and the LD50 for Shiga toxin is 250 ng/kg. Which of the following statements is true?
Shiga toxin is more lethal than staphylococcal enterotoxin.
Based on the following ID50 values, which microbe is the most virulent? Assume each bacterium enters through the appropriate portal of entry
Shigella: 10 cells
Define: Antimicrobial Peptides
Short peptides (12-50) produced in response to m/o binding to toll-like receptors
Why is inflammation beneficial?
Speeds up the immune system and gets white blood cells there faster repairs the damaged tissue
Types of Macrophages: Spleen
Splenic Macrophages
Which of the following virulence factors would be found in Staphylococcus aureus?
Staphylokinase
Which of these lists is in the correct order of differentiation?
Stem cells to B cells to plasma cells
The LD50 of Vibrio cholerae is 108 cells through the oral route. If the bacterial cells are ingested with bicarbonate, the LD50 drops to 104. Which of these explanations is the most likely
Stomach acid decreases the virulence of Vibrio cholerae
Define: Leukocidins
Substances produced by some bacteria that can destroy neutrophils and macrophages
A person who attended a picnic early in the day develops a very high fever and is unresponsive by the evening. This person most likely has been exposed to a(n)
Superantigen
How are superantigens different from other types of exotoxins?
Superantigens cause an overstimulation of the host immune system.
Classify portals of entry: Skin
Sweat gland duct, Hair follicles
Which of the following T cell is a component of both the cellular and humoral immune response?
T helper cells
Name: Mechanical Factors
Tears, Saliva, Urine, Peristalsis, Mucus
According to the video, for approximately how many days is IgG present in the serum?
Ten Days
Define: Pathogenicity
The ability of a microorganism to cause disease by overcoming the defenses of a host
Define: Adaptive Immunity
The ability, obtained during the life of the individual, to produce specific antibodies and T-Cells
Which of these conditions would NOT affect the ability of Streptococcus mutans to attach to teeth
The absence of actinomyces, a bacterium that can be part of dental plaque
Define: Lysogenic Conversion
The acquisition of new properties by a host c ell infected by a lysogenic phage
If a person turns their ankle, how would one determine if damage to the tissue in the ankle has occurred?
The ankle is red, swollen, and warm to the touch.
Which of the following most accurately describes how a pathogenic bacterium might be affected by antibodies?
The antibodies may block proteins necessary for binding the pathogen to the host, may opsonize the bacterium, or may agglutinate bacteria.
Define: Portal of Entry
The avenue by which a pathogen gains access to the body
Define: Toxigenicity
The capacity of a microorganism to produce a toxin
How does a capsule help certain bacteria evade detection by the immune system
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.
Define: Contact Inhibition
The cessation of animal cell movement a division as a result of contact with other cells
Define: Sclerotia
The compact mass of hardened mycelia of the fungus Claviceps purpurea that fills infected rye flowers: produces the toxin ergot
Define: Virulence
The degree of pathogenicity of a microorganism
The respiratory system is protected against harmful microbes by all of the following EXCEPT __________.
The lacrimal apparatus
Define: toxemia
The presence of toxins in the blood
Define: Portal of Exit
The route by which a pathogen leaves the bod
How is the secondary response different from the primary response in terms of antibody concentration in the blood?
The secondary response is faster and produces more antibodies than the primary response.
The specificity of an antibody is due to
The variable portions of the H and L chains
Which of these answers is a potential concern of using T-independent antigens as vaccines?
These antigens will be ineffective in producing an immune response in infants.
Define: Invasins
These microbial surface proteins rearrange the host cell's actin filaments, allowing pathogens to enter and move in and between cells.
Define: Toxins
These poisonous substances cause most of the damage to host cells; they can be transported by the blood or lymph and may produce far-reaching effects.
Define: Siderophores
These proteins bind up iron obtained from the host cell's iron-transport proteins and transport this iron to bacteria through interactions with cell surface receptors.
Define: Enzymes
These proteins contribute to a pathogen's virulence by, for example, forming and breaking down fibrin clots, breaking down connective proteins, and countering certain types of antibodies.
Define: Cell wall Components
These structures contain substances that contribute to a pathogen's virulence; for example, M protein mediates microbial attachment to epithelial cells.
What direct effect do histamines and leukotrienes have on capillaries?
They allow capillary walls to open and become leaky.
How are immune cells able to detect foreign pathogens?
They are able to detect structures on the surfaces of foreign cells that are not found in the host.
How do fibrinolysins enhance a pathogen's virulence?
They break down fibrin proteins that are involved in clot formation, allowing the cells to penetrate deep into damaged skin.
How do Shigella cells move between host cells?
They can polymerize actin molecules from the epithelial cells into tail-like structures that propel them from one cell to another.
How do superantigens enable pathogens to hide from the immune system if they actually stimulate the immune system?
They cause the immune system to produce an exaggerated response, distracting it from the actual pathogen
Which of the following statements is NOT true of antigens?
They often have a molecular weight of less than 10,000.
How do phagocytes communicate to other cells what they have captured?
They present antigens from engulfed foreign cells
Define: Direct Damage
This occurs as a result of nutrient depletion, accumulation of waste products, pathogen entry and exit, and ruptured host cells.
Define: Antigenic Variation
This process allows pathogens to alter their surface antigens to avoid attack by antibodies produced by the immune system.
Define: Cytopathic Effects
This results in a change in microbe characteristics due to the presence of prophage genes that confer new properties
Define: Lysogenic Conversion
This results in a change in microbe characteristics due to the presence of prophage genes that confer new properties
Define: Capsules
This viscous outer covering found in certain microorganisms helps pathogens evade the host's defenses by impairing phagocytosis.
What is the function of inflammation in response to a burn from a hot iron?
To repair the damaged tissue
What is TLR?
Toll-like receptor
__________ are involved in detecting foreign invaders. They do so by binding to pathogen- associated molecular patterns (PAMPs) on the surface of the pathogen.
Toll-like receptors
Name Iron-binding proteins
Transferrin, Lactoferrin, Ferritin, Hemoglobin
Define: Troll-like Receptor (TLP)
Transmembrane protein of immune cells that recognizes pathogens and activates an immune response directed against those pathogens
True/False Ergot and aflatoxin are toxins sometimes found in grains contaminated with fungi.
True
True/False Microorganisms that are members of the normal microbiota are also known to cause disease.
True
Which of the following microorganisms actually grows inside the macrophage
Tuberculosis bacterium
Each antibody has __________ antigen binding sites.
Two
The number of regions on an antibody molecule that can bind to an antigen is referred to as the __________ of that antibody.
Valence
When morning came, Caleb had not improved, so the Trappers took him to the pediatrician. A quick examination with the otoscope revealed the following : The examination led to a diagnosis of otitis media (OM), or an ear infection. The picture on the left demonstrates a swollen, red eardrum with a fluid buildup behind the membrane. The immune processes most involved in the inflammation seen behind Caleb's eardrum would be attributed to:
Vasodilation of capillaries and accumulation of immune cells, fluid or pus
Which of the following is the correct order of events after tissue damage during the process of inflammation?
Vasodilation; margination; diapedesis; phagocytosis
Define: Phagocytosis
When a white blood cell engulfs a pathogen and digests it using enzymes
When would endotoxins be released from a bacterial cell?
When the cell dies
Define: Compromised Host
Whose resistance to an infection is impaired by disease, therapy, or burns. Two principal conditions can compromise the host—broken skin or mucous membranes and a suppressed immune system.
The primary immune response involves
a slow rise in the concentration of antibodies, followed by a gradual decline.
Which of the following can defend the body by either opsonizing bacteria, lysing bacteria, and/or promoting inflammation?
alpha and beta interferons
An anamnestic response is
another name for secondary response.
Which of the following are best described as short chains of amino acids that are very stable and can have a variety of different antimicrobial activities, such as forming pores in bacterial plasma membranes and inhibiting cell wall synthesis?
antimicrobial peptides
In humans, where do B cells mature?
bone marrow
Which of the following is NOT a chemical factor that helps the skin to be relatively resistant to infection?
complement proteins
The epidermis __________.
contains the protein keratin
Define: Granulocytes
cytoplasm appears grainy when stained and viewed under a microscope
Define: Cytolysis
damages the invading cell membranes "member attach complex"
Pus is comprised of
dead phagocytes.
Define: Peristalsis
defecation or vomiting
Define: Nonspecific Resistance
defenses that protect the body from any pathogen
You note that the body temperature of one of your patients is starting to increase. As a result, you can infer that all of the following may be occurring in this patient EXCEPT __________.
dilation of blood vessels
One remarkable finding on a patient's laboratory workup is a marked eosinophilia. This might be suggestive of __________.
either a parasitic infection or an allergic (hypersensitivity) reaction
If one is examining a blood smear from a patient with a parasitic worm infection, which of the following leukocytes would be found in increased numbers?
eosinophils
Which of the following would be the first sign of an infection that resulted in the release of endotoxin?
fever
Define: Eosinophiles
first to enter the scene in response to a helminth infection - produces toxic proteins and peroxide ions
Antibiotics can lead to septic shock if used to treat
gram-negative bacterial infections
Define: Complement system
group of proteins activated when an antibody binds an antigen; enhances reaction against nonself substances
Define: Agranulocytes
has granulocytes, however they are not visible
Define: Inflammation
immunological response to cellular injury characterized by an increase in white blood cells. the release of histamine and vasodilation
water before covering it with a bandage. A short while later, Julie notices that her finger is red, swollen, warm to the touch, and very painful. Which of the following describes the process going on in Julie's finger?
inflammation
Define: a-IFN & b-IFN
interfere with viral multiplication - stimulates cells to produce antiviral proteins (AVP)
Antigen processing and presentation
is a way for a cell to give information about its activities.
Which of the following statements about sebum is NOT true?
it raises the pH of the skin
An inflammatory response would result from which of the following?
jellyfish sting
Line of Defense: Mucous Membrane
less protective than the skin, contains the GI lining, raspatory, reproductive tracks, and conjunctive '
Differential WBC count "increased" # of leukocytes
leukocytosis - Characteristic - meningitis, pneumonia, mono
Line of Defense: Skin
m/o cannot penetrate the skin. consists of dermis & epidermis
An individual may be exposed to a pathogen and become infected without actually getting sick. This is known as a subclinical infection. Even in subclinical infections, the individual's adaptive immune system can generate memory for the pathogen. What type of adaptive immunity is this?
naturally acquired active immunity
Define: Sebum
oily substance secreted by sebaceous glands
Inflammation cardinal sings
pain, heat, swelling, redness
A child falls and suffers a deep cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in eliminating contaminating microbes?
phagocytosis in the inflammatory response
As mentioned previously, the second line of defense is activated when the first line of defense fails. In Part A, you identified one of these defenses as inflammation, which occurs when the body responds to a foreign antigen and increases fluid accumulation in a specific area. An added benefit of this excess fluid is that it also brings immune cells to the area to aid clearance of foreign antigens. In Julie's situation, that added fluid would bring immune cells to prevent any microbial infections that could be caused if microbes were introduced when she cut her finger. Which of the following cell types is NOT part of the second line of defense?
plasma cells
What is in human blood
plasma contains (RBC/Leukocytes)
Define: y-IFN
produced by lymphocytes and stimulates neutrophiles to kill bacteria
Define: Perspiration
produced by the sweat glands contains lysozyme
Define: Basophils
release histamine; work in allergic responses
The Mucous Membrane secretes ________ that protect the host body
secretions
Inflammation is part of the second line of defense that is activated when the first line of defense is breached. Julie's first-line defenses were damaged when her injury occurred. Which of the following represents the first line of defense?
skin and mucous membranes
Define: Interferon's (IFN)
small proteins that are produced by cells in responses to infection protective to nearby uninfected cells
Measles viruses are capable of inactivating host defenses by
suppressing the immune system.
Define: Resistance
the body's ability to ward off disease through innate defenses
Define: Opsonization
the coating of a pathogen with a protein that facilitates phagocytosis interact with phagocytes to promote attachment and phagocytosis
Phagocytosis is defined as
the ingestion of solid material by a eukaryotic cell.
Define: Susceptibility
the lack of resistance
Emigration is
the migration of phagocytes through blood vessels to the site of tissue damage.
In which of the following cases would the Limulus amebocyte lysate (LAL) assay be used?
to ensure that a sterilized medical device is free of endotoxin
The function of the "ciliary escalator" is to
trap inhaled dust and microorganisms in mucus and propel it away from the lower respiratory tract.
The region of the antibody that binds the antigen is the ___________.
variable region
Certain traits that allow pathogens to create infection and cause disease are termed
virulence factors.
Define: Vasodilation
widening of blood vessels
