BMS 212 Exam 3 HW
What is a zoonosis? A disease caused by changes in the balance between normal microbiota A disease caused by normal human microbiota from the respiratory tract A disease caused by normal microbiota entering a body site where they do not normally occur A disease that spreads naturally from animals to humans
A disease that spreads naturally from animals to humans
A particular drug works by interfering with cellular metabolism in Gram-negative bacteria. How might these bacteria become resistant in a way that Gram-positive bacteria never could? Produce efflux pumps Alter drug targets Produce enzymes that alter the drug Alter porin proteins in the cell's outer membrane
Alter porin proteins in the cell's outer membrane
Which domain of the A-B toxin binds to cell surface receptors on the host cell? B domain A-B toxins do not bind to cell surfaces. Both the A and B domains have the ability to bind to cell surface receptors. A domain
B domain
An antimicrobial that inhibits bacterial cell wall synthesis will result in which of the following? Bacteria cannot attach to their hosts. The sterols in the bacterial cell wall become nonfunctional. Bacterial cells become more susceptible to osmotic pressure. Cytoplasmic membrane proteins lose their function. No change in bacterial cell activity.
Bacterial cells become more susceptible to osmotic pressure.
Why is autoclaving rather than boiling water used for sterilization? Autoclaving uses dry heat instead of water. Autoclaving is much faster than boiling water. Boiling water does not kill everything, including bacterial endospores and some protozoan cysts. Boiling water is too hot and may denature proteins.
Boiling water does not kill everything, including bacterial endospores and some protozoan cysts.
which of the following is cleaved by C1? C5 and C4 C4 C2 C2 and C4 C5
C2 and C4
which of the following is responsible for cleaving C3? C5bC6C7 C2aC4b C1 C4aC2b
C2aC4b
How can capsules enable bacteria to evade the immune system? A capsule is a superantigen that distracts the immune system. Capsules block the complement biding sites on the surface of the pathogen. Capsules can bind up IgA, rendering it inactive.
Capsules block the complement biding sites on the surface of the pathogen.
What is meant by selective toxicity? Chemotherapeutic agents should act against the pathogen and not the host. Chemotherapeutic agents should work on certain types of pathogens. Chemotherapeutic agents should have only one mode of action. Chemotherapeutic agents should work on many different targets on a pathogen.
Chemotherapeutic agents should act against the pathogen and not the host.
Quinolones and fluoroquinolones act against what bacterial target? Metabolic pathways unique to bacteria Bacterial ribosomes DNA gyrase Cell membranes Cell walls
DNA gyrase
What is diapedesis? Diapedesis occurs when white blood cells exit the bloodstream by squeezing between the cells that line the capillaries. Diapedesis occurs when inflammatory molecules are released from basophils. Diapedesis occurs when white blood cells take up foreign objects in order to destroy them. Diapedesis occurs when blood clots to stop wounds from bleeding.
Diapedesis occurs when white blood cells exit the bloodstream by squeezing between the cells that line the capillaries.
Which of the following does not spread drug resistance throughout a population of bacteria? Conjugation Efflux pumps Transduction Transformation
Efflux pumps
Which of the following phagocytic processes occurs last in the sequence? Formation of the phagolysosome Chemotaxis of the phagocyte to the site of infection Exocytosis Adherence
Exocytosis
Because all cells engage in protein synthesis, there are few antimicrobial drugs that selectively inhibit this process. True/False
False
In commensalism, one member of the relationship harms the other. True/False
False
The cell walls of mycobacteria make them vulnerable to water soluble chemical agents. True/False
False
The outer membrane of Gram-negative bacteria enables many antimicrobial drugs to enter the cell more easily. True/False
False
The resident microbiota have no role in defense against pathogen invasion. True/False
False
What does the plasma membrane of a phagocyte attach to on a microorganism? Glycoproteins Pseudopods Lysosomes Phagosomes
Glycoproteins
Why are chemotherapeutic agents that work on the peptidoglycan cell wall of bacteria a good choice of drug? The drugs also work against DNA gyrase. Humans and other animal hosts lack peptidoglycan cell walls. They are less expensive that other chemotherapeutic agents. Bacteria are especially sensitive to these compounds.
Humans and other animal hosts lack peptidoglycan cell walls.
The highest concentrations of medications are achieved by the (IM/IV/focal) route.
IV
What is the difference between the terms infection and disease? Infection means that a pathogen has adhered to the body's skin or mucous membranes, while disease means that the pathogen has invaded the body. Disease refers to the invasion of a pathogen into the body, while infection means that the body's normal function is disrupted. Infection refers to disease caused by microbes, while disease is the broader term used for any abnormal functioning of the body. Infection refers to the invasion of a pathogen into the body, while disease means that the body's normal function is disrupted.
Infection refers to the invasion of a pathogen into the body, while disease means that the body's normal function is disrupted.
Why is vasodilation important to tissue repair? It allows more nutrients to be delivered to the site of damage. It allows for an increase in oxygen to the site of damage. It allows more phagocytes to travel to the site of damage. It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage.
It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage.
Endotoxins are also known as Lipid A. prostaglandins. cytokines. interleukin-1.
Lipid A.
Which of the following situations is NOT a way in which a baby acquires normal microbiota? The baby acquires the residential microbiota in the colon after the first meal. Microbes enter the nose and mouth when the baby is in the birth canal. Staphylococcus epidermidis is transferred from the hospital staff to the newborn after delivery. Microorganisms grow in the respiratory tract after the baby's first breath. Microbes cross the placenta during pregnancy.
Microbes cross the placenta during pregnancy.
What are leukocidins? Molecules that are capable of destroying phagocytes Molecules that can degrade IgA Molecules that destroy the complement proteins
Molecules that are capable of destroying phagocytes
Symptoms are laboratory tests used to diagnose a disease. characteristics of a disease, such as sweating. objective manifestations of a disease that can be measured. subjective characteristics of a disease that only the patient can feel. objective manifestations of a disease that can be observed by others.
Objective characteristics of a disease that only the patient can feel.
Microbial molecules detected by phagocytes are called TLRs. prostaglandins. leukotrienes. NODs. PAMPs.
PAMPs.
Which antibiotic is overcome by beta-lactamases? Tetracycline Sulfonamide Penicillin Tetracycline, Penicillin, and Sulfonamide are all affected by beta-lactamase.
Penicillin
Why would an efflux pump for penicillin located on a bacterial cell membrane not be effective at providing resistance to the drug? The efflux pumps would not stop penicillin from blocking metabolic pathways. There are fewer efflux pumps on the cell membrane. The cell membrane is the target of penicillin. Penicillin disrupts the cell wall, which is located outside of the cell membrane.
Penicillin disrupts the cell wall, which is located outside of the cell membrane.
What cellular macromolecules make up the complement pathway? Nucleic acids Lipids Carbohydrates Proteins
Proteins
How is phagocytosis in the immune system different from protozoan phagocytosis? There is no difference between the two. Protozoan phagocytosis is used for feeding; phagocytosis by immune cells is used to fight infection. Protozoan phagocytosis is used to fight infection; phagocytosis by immune cells is used to feed the cells.
Protozoan phagocytosis is used for feeding; phagocytosis by immune cells is used to fight infection.
How are superantigens different from other types of exotoxins? Superantigens must be endocytosed into a target cell before becoming active. Superantigens cause an overstimulation of the host immune system. Superantigens comprise two functional domains. Superantigens only act against host neurons.
Superantigens cause an overstimulation of the host immune system.
Where are the complement proteins found in the body? The spleen The liver In every cell The blood serum The thymus
The blood serum
What effect do enterotoxins have? They kill any of the host cells they enter. They affect the nervous system. They are released from Gram-negative bacteria and can cause fever, inflammation, hemorrhaging, shock, and blood coagulation. They affect the gastrointestinal system.
They affect the gastrointestinal system.
What direct effect do histamines and leukotrienes have on capillaries? They decrease the diameter of capillaries. They prevent phagocytes from sticking to the walls of capillaries. They allow capillary walls to open and become leaky.
They allow capillary walls to open and become leaky.
Which of the following statements is TRUE of disinfectants? They are used on inanimate surfaces. They are only effective for short periods of time (seconds to minutes). They are used on living tissue. They are used for sterilization. They are effective in destroying endospores.
They are used on inanimate surfaces.
How do scientists ensure that autoclaved materials were actually sterilized? They may take a sample of the media being sterilized and inoculate it onto a plate for incubation. They inspect the materials under a microscope to search for contaminating microorganisms. There is no need to verify sterility when proper time, pressure, and temperature are maintained. They may place a sterility indicator with a special dye to detect the growth of endospores.
They may place a sterility indicator with a special dye to detect the growth of endospores.
Biofilms contribute to the spread of resistance to antimicrobials. True/False
True
By themselves, soaps have only degerming activity, not antimicrobial activity. True/False
True
Some bacterial cells are resistant to a variety of antimicrobials because they actively pump the drugs out of the cell. True/False
True
There are relatively few antifungal medications available compared to antibacterial drugs. True/False
True
A reservoir is a source of microbial contamination. a condition in which organisms remain in the body for a short time.an environment that is free of microbes. a source of microbes for laboratory testing. any microorganism that causes disease.
a source of microbial contamination.
Some bacteria are resistant to erythromycin as a result of mutation of their ribosomal RNA. What type of resistance does this represent? alteration of the target of the drug change in the permeability of the drug removal of the drug via a pump inactivation of the drug overproduction of an enzyme in a key metabolic pathway
alteration of the target of the drug
A (bacteriocidal/bacteriostatic/inhibitory) concentration of a drug is one at which microbes survive but are not able to grow and reproduce.
bacteriostatic
Which of the following can be used to reduce microbes in air? HEPA filters ethylene oxide ultraviolet light both HEPA filters and ultraviolet light both ethylene oxide and ultraviolet light
both HEPA filters and ultraviolet light
Disinfectants that damage membranes include phenolics. alcohol. hydrogen peroxide. iodine. both alcohol and phenolics.
both alcohol and phenolics.
Alcohols are used for sterilization. disinfection. antisepsis. both sterilization and disinfection. both antisepsis and disinfection.
both antisepsis and disinfection.
Quaternary ammonium compounds ("quats") are used for disinfection. antisepsis. sterilization. quantifying antimicrobial activity. both antisepsis and disinfection.
both antisepsis and disinfection.
Formalin (37% formaldehyde) is used for antisepsis. disinfection. sterilization. sanitization. both disinfection and sterilization.
both disinfection and sterilization.
Boiling water for 10 minutes is effective in ridding it of enveloped viruses. protozoan cysts. actively growing bacteria. bacterial endospores. both growing bacteria and enveloped viruses.
both growing bacteria and enveloped viruses.
Which of the following substances contributes to the edema associated with inflammation? defensin leukotrienes histamine interferon both leukotrienes and histamine
both leukotrienes and histamine
Protection from infection known as species resistance is a result of the lack of suitable environment in the body. the presence of phagocytes in the tissues. the absence of receptors required for microbial attachment. the salty, acidic condition of normal skin. both the absence of necessary receptors and lack of suitable environment in the body.
both the absence of necessary receptors and lack of suitable environment in the body.
The complement cascade and its by-products contribute to triggering inflammation and release of interferons. triggering inflammation. attracting phagocytes to sites of infection. triggering release of interferons. both triggering inflammation and attracting phagocytes to sites of infection.
both triggering inflammation and attracting phagocytes to sites of infection.
The process by which a phagocyte moves toward a chemical signal at the site of an infection is called digestion. elimination. exocytosis. chemotaxis. adherence.
chemotaxis.
An exotoxin that has the ability to kill or damage host cells is referred to as a(n) A-B toxin. cytotoxin. enterotoxin. superantigen. neurotoxin.
cytotoxin.
The physical removal of microbes is called (antisepsis/degerming/disinfection).
degerming
Which of the following proteins are part of the first line of defense against microbial invasion? TLRs dermcidins interferons NOD proteins C3 and C5
dermcidins
Leukocytes have the ability to cross the vessel wall out of the blood stream and into the tissues. This process is known as _____. phagocytosis diapedesis phagocytosis apoptosis
diapedesis
Hydrogen peroxide is an effective disinfectant. antiseptic. sterilizing agent. disinfecting and sterilizing agent. antiseptic and disinfectant.
disinfecting and sterilizing agent.
The antimicrobial polymyxin inhibits protein synthesis. blocks a metabolic pathway. disrupts cytoplasmic membranes. inhibits cell wall synthesis. inhibits nucleic acid synthesis.
disrupts cytoplasmic membranes.
Increased permeability of the vessels leads to _____ and pain. redness fever heat edema
edema
If a disease occurs at a fairly stable rate, it is said to be sporadic. endemic. pandemic. epidemic.
endemic.
Toxins that affect the lining of the digestive tract are (endotoxins/enterotoxins/exotoxins).
enterotoxins
Seventy percent alcohol is effective against non-enveloped viruses. prions. enveloped viruses. bacterial endospores. protozoan cysts.
enveloped viruses.
Heavy metal and oxidizing agent disinfectants damage (DNA/enzymes/membranes), interfering with microbial metabolism.
enzymes
Which of the following cells increase in number during an infection with parasitic worms? macrophages neutrophils basophils eosinophils lymphocytes
eosinophils
The antifungals known as polyenes interact with ________, a lipid unique to fungus membranes. ergosterol cholesterol glycolic acid phospholipid mycolic acid
ergosterol
Which of the following is used to sterilize items that should not, or cannot, be exposed to heat or water? formaldehyde calcium hypochlorite ethylene oxide triclosan hydrogen peroxide
ethylene oxide
Part complete Intact skin layers are part of the body's (first/second/third) line of defense against pathogens.
first
Which of the following drugs inhibits nucleic acid synthesis specifically in most bacteria? fluoroquinolones 5-fluorocytosine tetracycline rifampin actinomycin
fluoroquinolones
Which of the following are among the activities of neutrophils? release of histamines formation of neutrophil extracellular traps enzyme production that leads to the formation of nitric oxide formation of neutrophil extracellular traps and release of histamines formation of neutrophil extracellular traps and production of nitric oxide
formation of neutrophil extracellular traps and production of nitric oxide
Aseptic means sanitized. free of pathogens. free of all microbes. clean. sterile.
free of pathogens.
A chemical agent that kills pathogenic microbes in general is a(n) disinfectant. sanitizer. germicide. fungicide. antiseptic.
germicide.
In a process called (cytokinesis/hematopoiesis/hematocrit), blood stem cells located in the bone marrow produce the three types of formed elements found in the blood.
hematopoiesis
A patient is infected with a bacterium that produces the enzyme beta-lactamase; this enzyme inactivates penicillins, carbapenems, and cephalosporins. acts in conjugation. allows for transduction. prevents entrance of an antimicrobial drug into a cell.
inactivates penicillins, carbapenems, and cephalosporins.
Fomites are inanimate objects involved in the indirect contact transmission of pathogens. fecal material from infected hosts. insects that transmit pathogens from an infected host to an uninfected host. animal sources for human pathogens. silent carriers of infectious diseases.
inanimate objects involved in the indirect contact transmission of pathogens.
Fever is beneficial during viral infection because the higher temperature increases the effectiveness of interferons. increases vasodilation, contributing to inflammation. increases sweating and consequently the barrier effect. prevents viral infection of fibroblasts. inactivates interferons.
increases the effectiveness of interferons.
The (incubation/morbidity/prodromal) period is the time between infection and the occurrence of the first symptoms or signs of the disease.
incubation
Most broad-spectrum antibiotics act by inhibiting protein synthesis. inhibiting metabolic pathways. inhibiting the synthesis of the cell wall. disrupting the cytoplasmic membrane. inhibiting nucleic acid synthesis.
inhibiting protein synthesis.
Which of the following is NOT a mode of action of antimicrobial drugs? inhibition of flagella formation inhibition of cell wall synthesis inhibition of protein synthesis inhibition of nucleic acid synthesis
inhibition of flagella formation
The first and second lines of defense against microbial invasion are part of adaptive immunity. species resistance. innate immunity. microbial antagonism. species immunity.
innate immunity.
Which of the following is the first line of defense? nonspecific leukocytes secreting toxins onto the surface of virally infected cells phagocytes intact skin, mucous membranes, sebum, tears, and sweat histamine, prostaglandin and leukotriene production the coating of a pathogen by complement
intact skin, mucous membranes, sebum, tears, and sweat
Which of the following drugs specifically targets cell walls that contain mycolic acid? isoniazid bacitracin methicillin vancomycin penicillin
isoniazid
Ultraviolet light penetrates (more/less) effectively than gamma rays.
less
White blood cells known as (basophils/lymphocytes/neutrophils) are the main cells involved in the third line of defense.
lymphocytes
Sweat glands produce (lysozyme/dermcidin/acid), which destroys the cell wall of bacteria by cleaving the bonds between the sugar subunits.
lysozyme
What antibacterial chemical is present in tear fluid? complement antibodies defensins lysozyme interferon
lysozyme
Basophils, platelets, and _____ are all capable of secreting histamines. monocytes neutrophils mast cells complement
mast cells
Which cell becomes a macrophage when leaving the bloodstream? lymphocyte basophil monocyte neutrophil eosinophil
monocyte
Microbes known as transient microbiota are microorganisms that remain with the person throughout life. unsuccessful microbial invaders because of the presence of preexisting microbes. microorganisms that may cause a disease under certain circumstances. sources of microbial contamination. organisms that remain in the body for a short time.
organisms that remain in the body for a short time.
Damage to the cell wall will adversely affect a bacterial cell by making it more susceptible to __________. osmotic pressure alcohols high temperature radiation
osmotic pressure
Chagas' disease is transmitted by a bug with mouthparts that penetrate blood vessels. Which type of exposure does this represent? parenteral route contact fomite skin portal mucous membrane portal
parenteral route
TLRs are the coatings of pathogens by complement. molecules that damage cells, resulting in cell lysis. phagocyte receptors that detect PAMPs. nonspecific leukocytes that secrete toxins onto the surface of virally infected cells. present in intact skin, sebum, tears, etc.
phagocyte receptors that detect PAMPs.
Infectious agents known as (endospores/cysts/prions) are the most resistant to antimicrobial agents or processes.
prions
The tetracyclines interfere with cell membrane component synthesis. protein synthesis. cell wall synthesis. folic acid synthesis. nucleic acid synthesis.
protein synthesis.
Which of the following groupings contain things that are all true indicators of inflammation? blueness, coolness, edema, pain redness, heat, edema, pain redness, coolness, numbness, fever redness, heat, edema, pain, fever
redness, heat, edema, pain
An antimicrobial disk on a Kirby-Bauer plate that shows no zone of inhibition indicates that the microbe being tested is __________ to the drug. susceptible intermediate synergistic resistant
resistant
The oily substance that lowers the pH of the skin's surface to about pH 5 and is inhibitory to many bacteria is (sebum/sweat/serum).
sebum
A compound is extracted from a microbial culture and is modified in the laboratory for use as an oral medication. This product would be a(n) antibiotic. synthetic antimicrobial. probiotic. analog. semisynthetic antimicrobial.
semisynthetic antimicrobial.
The absence of necessary receptors is the basis of the defense against microbial invasion known as (natural/innate/species) resistance.
species
A drug is structurally similar to PABA and inhibits folic acid synthesis. It is most likely a(n) azole. nucleic acid analog. sulfonamide. penicillin. tetracycline.
sulfonamide.
Secondary infections that result from the killing of some of the normal microbiota are called (antagonism/superinfections/resistance).
superinfections
Which of the following groups of drugs can become incorporated into the bones and teeth of a fetus? quinolones beta-lactams aminoglycosides sulfonamides tetracyclines
tetracyclines
Opsonization is the sticking of monocytes to the wall of the blood vessels at the site of infection. phagocyte receptors detecting PAMPs. the coating of a pathogen by complement to facilitate phagocytosis. nonspecific leukocyte secretion of toxins onto the surface of virally infected cells. damage resulting in cell lysis.
the coating of a pathogen by complement to facilitate phagocytosis.
Expected prevalence of a disease is the total number of cases of a disease over a period of time. the expected occurrence of a disease based on past observations. the anticipated geographical spread of a disease based on past observances. the number of new cases of a disease over a period of time.
the expected occurrence of a disease based on past observations.
Which of the following stages of an infectious disease is the most severe? the illness period the incubation period the prodromal period the convalescence period the decline period
the illness period
Phagocytosis is defined as the ingestion of solid material by a eukaryotic cell. cells of the immune system that ingest pathogens. the uptake of liquid material by a eukaryotic cell. the feeding of protozoans.
the ingestion of solid material by a eukaryotic cell.
What is the purpose of an autoclave? to warm up cultures to sterilize equipment and media to wash equipment to incubate cultures
to sterilize equipment and media
Selective (action/toxicity/treatment) means that a given antimicrobial agent is more toxic to a pathogen than to the host being treated.
toxicity
The process of acquiring antibiotic resistance by means of bacteriophage activity is called transduction. R-plasmid acquisition. point mutation. transformation.
transduction.
Which of the following types of radiation is non-ionizing and has the shortest wavelength? microwaves X rays infrared radiation ultraviolet light gamma rays
ultraviolet light
Which of the following is NOT a feature associated with filtration? ability of some filters to trap viruses and proteins use of HEPA filters to filter air sterilization of heat-sensitive materials varying thicknesses of membrane filters used nitrocellulose or plastic membrane filters
varying thicknesses of membrane filters used
Inflammatory mediators such as bradykinin and histamine cause blood vessels to _____. increase permeability vasodilate vasoconstrict lengthen
vasodilate
The degree to which a microbe is able to cause disease is known as its (morbidity/virulence/toxicity).
virulence