Microbiology Chp. 5 review
A suffix used to describe a killing action would be A. -static. B. -cidal. C. -cillin. D. -tion.
-cidal.
In a one D process, how many D values would it take to reduce a population of 1010 cells to one survivor? A. 2 B. 4 C. 5 D. 10
10
Typical conditions used for sterilization are A. 100°C for 10 minutes. B. 121°C at 15 psi for 15 minutes. C. 80°C for 15 minutes. D. 72°C for 15 seconds.
121°C at 15 psi for 15 minutes.
If a process kills 90% of the organisms per minute, how many minutes would it take to kill all organisms when starting with 100,000 organisms? A. 1 minute B. 2 minutes C. 3 minutes D. 6 minutes
6 minutes
Which enzyme drives ATP synthesis? a. ATP synthase b. ADP phosphorylase c. proton movies d. oxidoreductase
ATP synthase
Chemical germicides A. may react irreversibly with proteins/enzymes. B. may react with cytoplasmic membranes or viral envelopes. C. may be disinfecting or even sterilizing. D. are sensitive to dilution factor, time of contact, and temperature of use. E. All of the choices are true.
All of the choices are true.
Chemolithotrophs near hydrothermal vents support a variety of life forms. Why is the analogous to photosynthetic microbes supporting life forms closer to the surface of the planet?
Because all life forms need some energy source, electron source and carbon source ETC.
Select the incorrectly matched pair. a. Bacterial endospores- highly resistant b. d-valve- time to destroy 10%of microbes present c. Critical instrament- scaples and needles d. incineration- burns cells to ashes
D-valce- time to destroy 10% of microbes present
the TCA cycle produces a. ATP, FAD, and precursor metabolites b. NADH, ATP, and FAD c. FADH2, NADH, and precursor metabolites d. FADH2, ADP, and NADH e. precursor metabolites, NAD, and FADH2
FADH2, NADH, and precursor metabolites
100% ethanol is twice as effective as 60% ethanol at controlling bacteria. True False
False
Cold and freezing are very effective in killing bacteria. True False
False
Dry heat takes a much shorter time to sterilize material than wet heat. True False
False
Heat treatment is an effective method for sterilization or disinfection of all materials. True False
False
Hydrogen peroxide may be used as a sterilant on living tissue. True False
False
Pasteurization results in the sterilization of food products. True False
False
Prions and viroids are easily destroyed by common sterilization procedures. True False
False
The endospores of Pseudomonas make that organism very difficult to kill. True False
False
Which of the following is true of hydrogen peroxide? A. It is a sterilant for inanimate objects and is quickly inactivated on living tissue. B. It leaves a toxic residue. C. It is broken down by catalase into water and oxygen. D. It is even more effective when used in combination with peracetic acid. E. It is a sterilant for inanimate objects and is quickly inactivated on living tissue; it is broken down by catalase into water and oxygen AND it is even more effective when used in combination with peracetic acid.
It is a sterilant for inanimate objects and is quickly inactivated on living tissue; it is broken down by catalase into water and oxygen AND it is even more effective when used in combination with peracetic acid.
Hand washing with plain soap is very effective in controlling spread of microorganisms because.... a. Plain soap is bacteriostatic and inhibits bacterial growth b. it is very effective in the mechanical removal go microorganisms c. all soaps are virucidal and kill all viruses d. pain soap is bactericidal and kills bacteria
It is very effective in the mechanical removal of microorganisms
A student argued that aerobic and anaerobic respiration should produce the same amount of energy. He argued that both processes are essentially the same-only the terminal electron acceptor is different. What's wrong with his argument?
Not all electron acceptors are the same ETC
Lister developed his idea on prevention of infection during medical procedures after studying the work of a. koch b. pasteur c. jenner d. flemming
Pateur
A common environmental organism that may even grow in certain chemical disinfectants is A. Escherichia coli. B. Streptococcus pneumoniae. C. Pseudomonas aeruginosa. D. enveloped virus.
Pseudomonas aeruginosa.
Hexachlorophene has been particularly effective against A. Staphylococcus aureus. B. Micrococcus aureus. C. Escherichia coli. D. Enterobacter aerogenes.
Staphylococcus aureus.
Boiling is very effective at removing most common waterborne pathogens. True False
True
Generally, heavy metals, except silver, have been proven to be too toxic for use on human tissue and are no longer used medically. True False
True
Organic acids, such as benzoic acid, are often added to foods to prevent microbial growth. True False
True
The more bacteria ones starts with, the longer it will take to kill them all. True False
True
Upon heat treatment, bacteria die at a constant proportion. True False
True
Which of the following methods sterilize the materials? A. Pasteurization B. High-temperature-short-time pasteurization (HTST) C. Ultrahigh-temperature (UHT) method D. None of these are sterilization methods
Ultrahigh-temperature (UHT) method
Which of the following generates the greatest amount of energy? a. fermentation b. aerobic respiration c. Krebs cycle d. glycolysis
aerobic respiration
oxygen serves as the terminal electron acceptor in a. fermentation b. aerobic respiration c. anaerobic respiration d. reduction
aerobic respiration
Which are true coenzymes? a. they are organic molecules b. they transfer atoms from one molecule to another c. they may bind to a number of different enzymes d. they are synthesized from vitamins e. all of the answers are correct
all are correct
to reduce or eliminate disease/spoilage causing organisms, foods is often subjected to a. heat b. chemical additives c. radiation d. cold e. all are correct
all are correct
Which of the following are considered when selecting a germicidal chemical a. toxicity and cost b. cost and compatibility with the material being treated c. compatibility of the material being treated and environmental impact d. environmental impact, toxicity and cost e. all of the answers are correct
all of the answers are correct
which is true regarding the three central metabolic pathways? a. they form high energy bonds that can be used to synthesize atp b. they form intermediates that can be oxidized to generate reducing power c. they form precursor metabolites d. all of the answers are correct
all of the answers are correct
microbial death rates may be affected by a. ph b. temperature c. the presence of organics d. growth in a biofilm e. All of the choices are correct
all of the choices are correct
for use on skin
antiseptic
Nosocomial infections A. are acquired at various social events. B. are acquired while in the hospital by susceptible people. C. they occur in communities but very seldom in hospitals. D. are acquired at sporting events. E. they occur most frequently in isolated communities.
are acquired by susceptible people in the hospital.
Commercial canning processes A. are geared to destroy Clostridium botulinum spores. B. kill all endospores. C. are especially needed on low acid foods. D. are 12D processes. E. are geared to destroy Clostridium botulinum spores, are especially needed on low acid foods, AND are 12D processes.
are geared to destroy Clostridium botulinum spores, are especially needed on low acid foods, AND are 12D processes.
Most enzymes a. are generic, typically recognizing a number of different substrates b. are specific, typically recognizing a single or few substrates c. are active over wide ph range d. are active over a wide temperature range e. are unaffected by heat or activity
are specific, typically recognizing a single or few substrates
The term "precursor metabolite" refers to molecules that a. activate cell components b. are used in biosynthesis c. result from cell activities d. are present but inactive e. denature enzymes
are used in biosynthesis
Please select the true statement regarding preservation of perishable products. a. nitrites and nitrates are always converted into carcinogens by intestinal bacteria b. refrigeration destroys most pathogens and all spoilage microorganisms c. salting and drying increase the avaliablilty of water in food above the limits required d. drying stops microbial growth and reliably kills all bacteria and fungi in or on foods e. bacterial resistance to some of the chemicals included to perishable products has been reported
bacterial resistance to some of the chemicals included to perishable products has been reported
mercury in mercurochrome inhibits growth a. through competitive inhabitation b. through reversible action c. by oxidizing the sulfhydryl groups in cysteine d. by changing the shape of proteins e. by oxidizing the sulffhydryl groups in cysteine and by changing the shape of proteins
by oxidizing the sulffhydryl groups in cysteine and by changing the shape of proteins
Gamma irradiation A. has not been approved for use on food. B. can be used to either sterilize or pasteurize, depending on the dose of radiation. C. leaves some radioactive particles in the treated substance. D. usually kills by disrupting cell membranes.
can be used to either sterilize or pasteurize, depending on the dose of radiation.
One of the first chemicals used by Lister to prevent surgical sepsis was A. alcohol. B. iodine. C. carbolic acid. D. mercury.
carbolic acid.
Quaternary ammonium compounds are A. cationic detergents which help wash surfaces. B. attracted to the negative charge on the microbial cell surface. C. used as a 37% aqueous solution. D. very effective against Pseudomonas. E. cationic detergents which help wash surfaces AND attracted to the negative charge on the microbial cell surface.
cationic detergents which help wash surfaces.
Ultraviolet radiation at the bactericidal wavelength destroy bacteria by A. destroying endospores. B. damaging nucleic acid. C. preventing spore formation. D. denaturing proteins.
damaging nucleic acid.
Phenolics A. denature proteins and destroy cytoplasmic membranes. B. remain effective in the presence of detergents or organic material. C. such as triclosan, have been used widely in various lotions and soaps. D. reliably inactivate all groups of viruses. E. denature proteins and destroy cytoplasmic membranes, remain effective in the presence of detergents or organic material, AND phenolics such as triclosan, have been used widely in various lotions and soaps.
denature proteins and destroy cytoplasmic membranes, remain effective in the presence of detergents or organic material, AND phenolics such as triclosan, have been used widely in various lotions and soaps.
Upon treatment with heat or chemicals, bacteria will A. all die immediately. B. die at a constant proportion. C. die at an exponential rate. D. die at a geometric rate.
die at a constant proportion.
use of heat to eliminate pathogens/spoilage organisms
disinfection
Which are essentially equivalent treatments? A. dry 200°C heat for 1.5 hours; wet 121°C heat for 15 minutes B. dry 160°C heat for 1.0 hours; wet 200°C heat for 30 minutes C. dry 121°C heat for 1.5 hours; wet 200°C heat for 15 minutes D. dry 100°C heat for 2.0 hours; wet 100°C heat for 30 minutes
dry 200°C heat for 1.5 hours; wet 121°C heat for 15 minutes
Which of the following are resistant to disinfection by typical disinfection methods? a. Endospores of Bacillus and Clostridium b. escherichia c. enveloped viruses d. mycoplasma species
endospores of bacillus and clostridium
the use of the suffix "ase" on a word denotes a a. substrate b. product c. enzyme d. electron acceptor
enzyme
Generally, membrane filters are not used to remove A. bacteria from liquids. B. microorganisms from gases. C. spoilage agents from alcoholic beverages. D. enzymes from liquids. E. bacteria from nutrient broths.
enzymes from liquids
Pyruvate can be metabolized along two major routes. They are a. oxidation and reduction b. fermentation and respiration c. metabolism and anabolism d. anabolism and catabolism e. fermentation and oxidations
fermentation and respiration
Fermentation if often used as a means of slowing food spoilage. Why would fermentation lead to this outcome?
fermentation will lead to production of acidic by-products, dropping the ph of the food below a level that bacteria can tolerate.
Boiling is not reliable for sterilization because A. heat sensitive instruments may be destroyed. B. heat resistant endospores are unaffected. C. water boils at a higher temperature at lower altitudes. D. viruses are more sensitive to heat than bacteria.
heat resistant endospores are unaffected.
The autoclave treatment may be monitored by A. heat-sensitive tape. B. heat-resistant endospores of Geobacillus stearothermophilus. C. pressure indicators alone. D. waiting for contaminants to appear on freshly poured media. E. heat sensitive tape AND heat-resistant endospores of Bacillus stearothermophilus.
heat sensitive tape AND heat-resistant endospores of Bacillus stearothermophilus.
Oxidation of proteins is achieved most readily A. by moist heat. B. by moist heat under pressure. C. in a hot air oven. D. in the presence of organics.
in a hot air oven.
The most important function of nitrites in processed foods is to A. prevent browning. B. inhibit the germination of Clostridium botulinum endospores. C. prevent carcinogen formation. D. make the food more acidic.
inhibit the germination of Clostridium botulinum endospores.
Moist heat kills microorganisms by A. irreversible coagulation of proteins. B. destruction of carbohydrates in the cell wall. C. denaturation of nucleic acids. D. dissolving the capsule.
irreversible coagulation of proteins.
Chlorhexidine a. is an aldehyde b.is extensively used in antiseptics c. is ineffective against vegetable bacteria d. is limited in use due to its high toxicity
is extensively used in antiseptics
free energy a. is the amount of energy gained by breaking bonds of a chemical b. includes the energy lost as heat c. differs for a given reaction depending on the number of steps involved d. always results in a decrease in total energy e. is the amount of energy lost by breaking bonds of a chemical
is the amount of energy gained by breaking bonds of a chemical
Pasteurization a. is the use of heat to sterilize food products b. is a process that uses intensive cold to kill organisms on food c. is the use of heat to reduce numbers of pathogenic/spoilage bacteria in a food item to a safe level d. is a process that uses short bursts of radiation to kill microorganisms on food
is the used of heat to reduce numbers of pathogenic/spoilage bacteria in a food item to a safe level
the energy field of any energy transforming pathway a. is always fixed, despite the removal of precursor metabolites for biosynthesis b. is variable depending on the type of enzymes used c. is variable depending on the amount of precursor metabolites removed for biosynthesis d. is fixed by the amount of oxygen available e. is fixed by the amount of carbon dioxide available
is variable depending on the amount of precursor metabolites removed by biosynthesis
Glutaraldehyde a. is very good for use on heat-sensitive medical items b. inactivates lipids c. does not affect non-developed viruses d. is used in gaseous form e. kills bacteria but does not affect endospores
is very good for use on heat-sensitive medical items
Ethylene oxide is gas that A. is very useful for sterilizing heat or moisture sensitive items. B. is potentially carcinogenic. C. is used as a 37% aqueous solution. D. is effective against all microorganisms except endospores and viruses. E. is very useful for sterilizing heat or moisture sensitive items AND is potentially carcinogenic.
is very useful for sterilizing heat or moisture sensitive items AND is potentially carcinogenic.
Please select the false statement regarding hydrogen peroxide a. it is a sterilant for inanimate objects and is quickly inactivated on living tissue b. it leaves no toxic residue and is safe on materials such as glass and plastic c. it is broken down by catalase into water and oxygen d. it is even more effective when used in combination with peracetic acid e. it immediately kills all bacteria when applied to a wound
it immediately kills all bacteria when applied to a wound
Which is true of iodine? a. it readily kills endospores b. it may be used as an antiseptic but not as a disinfectant c. it can be used at any dilution d. it is usually found as tinctures or iodophors e. it may be used as a disinfectant but not as an antiseptic
it is usually found as tinctures or iodophors
Glycolysis a. requires oxygen b. may occur under aerobic or anaerobic conditions c. produces 3 ATP molecules per molecule glucose d. produces 4 molecules of NAD per molecule glucose e. always occurs under aerobic conditions
may occur under aerobic or anaerobic conditions
Liquid media containing heat-sensitive components would best be sterilized by A. Ultraviolet (UV) light at 500 nm B. freezing. C. lyophilization. D. membrane filtration.
membrane filtration.
the general term used to describe the anabolic and catabolic reactions in a cell is a. enzymatic b. thematic c. aerobic respiration d. metabolism e. canabolism
metabolism
A sterile item is free of A. microbes, endospores and prions B. prions only. C. viruses, endospores and prions D. microbes, viruses, and prions E. microbes, endospores, and viruses.
microbes, endospores AND viruses.
An atom that has a lower affinity for electrons than another is _________ than the other. a. more electronegative b. less electronegative c. equally electronegative d. more electropositive
more electronegative
Alcohols are not reliably effective at destroying A. vegetative bacteria and endospores. B. enveloped viruses and endospores. C. non-enveloped viruses and enveloped viruses. D. non-enveloped viruses and endospores. E. non-enveloped virsues and vegitative cells.
non-enveloped viruses AND endospores.
Which of the following is not a sterilization method? A. hot air oven B. autoclave C. pasteurization D. filtration
pasteurization
elimination of most pathogens on a material
pasteurization
silver sulfadiazine, a combination of silver and sulfa drug, is used to a. disinfect water for drinking b. prevent infection of surgical wounds c. prevent infection of second and third degree burns d. counteract lead poisoning
prevent second and third degree burns
Gamma rays cause biological damage in living systems by A. producing reactive molecules such as superoxide and hydroxyl free radicals. B. causing tiny gravity sinks and black holes to be formed in the substance. C. introducing toxins. D. making the substance radioactive.
producing reactive molecules such as superoxide and hydroxyl free radicals.
a common environmental organism that may even grow in certain chemical disinfectants is a. escheria coli b. streptococccus pneumoniae c. pseudomonas aeruginosa d. influenza virus (enveloped)
pseudomonas aeruginosa
Which would be most effective against Pseudomonas? A. alcohol B. radiation C. quaternary ammonium compounds D. iodophors E. Hand soap
radiation
Chlorine a. readily acts with organics to produce potentially carcinogenic trihalomethanes b. is expensive but is able to destroy all types of microorganisms c. is unaffected bu the presence of organic materials d. is ineffective when diluted
readily acts with organics to produce potentially carcinogenic trihalomethanes
Chlorine A. readily reacts with organics to produce potentially carcinogenic trihalomethanes. B. is an effective, inexpensive, disinfectant able to destroy all types of microorganisms. C. is unaffected by the presence of organic material. D. is ineffective when diluted. E. readily reacts with organics to produce potentially carcinogenic trihalomethanes AND is an effective, inexpensive, disinfectant able to destroy all types of microorganisms.
readily reacts with organics to produce potentially carcinogenic trihalomethanes AND is an effective, inexpensive, disinfectant able to destroy all types of microorganisms.
the name given to a reactions involving the addition of electrons or hydrogen atoms to a compound is a. reduction b. glycolysis c. oxidation d. metabolism e. respiration
reduction
the electron transport system a. requires a membrane and requires mitochondria and ribosomes b. uses the nuclear membrane of eukaryotes and generates a concentration gradient of protons c. requires a membrane and generates a concentration gradient of protons d. uses the mitochondria membrane of prokaryotes and generates a concentration gradient of protons
requires a membrane and generates a concentration gradient of protons
reduction of microorganisms to meet health standards
sanitization
most enzymes function best at a. acidic ph and high salt concentrations b. basic ph and low salt concentrations c. slightly above ph 7 and low salt concentration d. neutral ph and high salt concentration e. slightly above ph 7 and high salt concentrations
slightly above ph 7 and low salt concentration
The process of killing or removing all the microorganisms in or on a material is termed A. sterilization. B. disinfection. C. sanitation. D. antisepsis.
sterilization
removal of all life
sterilization
a common application of dry heat in the micro lab is to a. prepare specimens for study b. steralize media c. sterilize plastics d. sterilize the inoculating loop
sterilize the inoculating loop
A common application of dry heat in the laboratory is to A. prepare specimens for study. B. sterilize media. C. sterilize plastics. D. sterilize the inoculating loop.
sterilize the inoculating loop.
Which is false regarding glycolysis a. it yields amp b. it is an anaerobic process c. the end product is acetyl- CoA d. it occurs during fermentation
the end product is acetyl- CoA
Which statement about catabolism and anabolism is true? a. they refer only to the reactions dealing involved in the metabolism of lipids b. the intermediates of catabolism serve as products in anabolism c. the energy gathered during catabolism is used during anabolism d. they refer only to the reactions involved in carbohydrate synthesis
the energy gathered during catabolism is used during anabolism
Microwaves do not kill organisms directly but kill by A. the heat they generate in a product. B. generating free radicals. C. generating toxins. D. creating thymine dimers.
the heat they generate in a product.
Compounds of tin, mercury, arsenic, and copper are no longer used to prevent microbial growth in cooling water primarily because A. antibiotics are cheaper. B. other chemicals were shown to be much more effective. C. microbes developed resistance to these metals. D. their use contributes to serious pollution of natural waters. E. All of the choices are correct.
their use contributes to serious pollution of natural waters.
Substrate refers to a substance on which an enzyme acts to form products or a surface on which an organism can grow
true
Fermentation a. uses an organic molecule as the final electron acceptor. b. results in the production of a large amount of ATP. c. is necessary in some organisms to produce reduced electron carriers. d. uses an organic molecule as the final electron acceptor AND is necessary in some organisms to produce reduced electron carriers. e. uses an inorganic molecule as the final acceptor
uses an organic molecule as the final electron acceptor
In order to speed up the sterilization process, which of the following would be useful? A. drying the material B. washing/mechanical removal of bacteria/organic matter C. addition of organics D. nothing E. washing/mechanical removal of bacteria/organic matter AND addition of organics
washing/mechanical removal of bacteria/organic matter
in the photographic production of energy, the oxygen originates from a. carbon dioxide b. water c. glucose d. hydrogen peroxide
water