Lister developed his ideas on asepsis after studying the work of

a. Koch.

b. Pasteur.

c. Jenner.

d. Fleming.

One of the first chemicals used by Lister to prevent surgical sepsis was

a. alcohol.

b. iodine.

 c. carbolic acid.

d. mercury.

The process of killing or removing all the microorganisms in or on a material is termed

a. sterilization.

b. disinfection.

c. sanitation.

d. antisepsis.

A sterile item is free of

a. microbes.

b. endospores.

c. viruses.

d. prions.

e. a, b and c

A suffix used to describe a killing action would be

a. -static.

b. -cidal.

c. -cillin.

d. -tion.

Pasteurization

a. is the use of heat to sterilize food products.

b. is the use of heat to reduce pathogenic/spoilage bacteria to a safe level.

c. is a process which uses intense cold to kill microorganisms on foods.

d. is a process which uses short bursts of radiation to kill microorganism on foods.

Which of the following organisms are resistant to destruction by typical control methods?

a. endospores of Bacillus and Clostridium

b. Pseudomonas

c. naked viruses

d. Mycobacterium spp.

e. all of the above

Plain soap is very effective in controlling spread of microorganisms because it is

a. bacteriostatic.

b. very effective at the mechanical removal of microorganisms.

c. virucidal.

d. bactericidal.

Nosocomial infections

 a. are acquired at various social events.

b. are acquired while in the hospital.

c. occur because of a susceptible population and presence of disease causing organisms.

d. are acquired at sporting events.

e. b and c

To reduce or eliminate disease/spoilage causing organisms, food is often subjected to

a. heat.

 b. chemical additives.

c. radiation.

d. cold.

e. all of the above

Which of the following organisms is most resistant to chemical treatment?

a. Streptococcus pneumonia

b. Salmonella typhi

c. Bacillus cereus

d. Mycobacterium tuberculosis

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.

Upon treatment with heat or chemicals, bacteria will

a. all die immediately.

b. die at a constant rate.

c. die at an exponential rate.

d. die at a geometric rate

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

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

Microbial death rates may be affected by

a . pH.

b. temperature.

c. the presence of organics.

d. all of the above.

The greatest hindrance to germicidal activity of a chemical agent is

a. the quality of the container.

b. the temperature.

c. the presence of organic matter.

d. the personnel performing the duty.

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. b and c

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.

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.

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.

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

Which of the following is not a sterilization method?

a. hot air oven

b. autoclave

c. pasteurization

d. filtration

Flash autoclaving uses

a. 100 °C for 5 minutes.

b. 121 °C for 15 minutes. c

. 135 °C for 3 minutes.

d. 121 °C for 15 minutes.

The autoclave treatment may be monitored by

a. heat-sensitive tape.

b. heat-resistant endospores of Bacillus stearothermophilus.

c. pressure indicators alone.

d. waiting for contaminants to appear on freshly poured media.

e. a and b

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. a, c and d

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.

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

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 above are true

Alcohols are not reliably effective at destroying

 a. vegetative bacteria.

 b. enveloped viruses.

c. naked viruses.

d. endospores.

e. c and d

Glutaraldehyde

a. is, if given enough time, able to destroy all forms of microbial life.

b. is very good for use on heat-sensitive medical items.

c. attacks lipids.

d. does not affect naked viruses.

e. a and b

Glutaraldehyde

            a. is, if given enough time, able to destroy all forms of microbial life.

            b. is very good for use on heat-sensitive medical items.

            c. attacks lipids.

            d. does not affect naked viruses.

            e. a and b

e

A is if given enought time able to destroy all forms of microbial life and

b is avery good for use on heat-sensitivie medical items

Which of the following is not used as a gas in the destruction of microorganisms?

a. ethylene oxide

b. chlorine

c. phenol

d. formaldehyde

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. a and b

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. a and b

Which is true of iodine?

a. It does not readily kill endospores.

b. It may be used as an antiseptic or as a disinfectant.

c. It is important to use it at the recommended dilution.

d. It is usually found as tinctures or iodophors.

e. all of the above are true

Currently the use of 1% silver nitrate in newborns eyes has been replaced with

a. 2% silver nitrate.

b. alcohol drops.

c. saline flushes.

d. antibiotics.

The eyes of newborns are treated with antibiotics to protect from infection with

 a. Streptococcus pyogenes.

b. Neisseria gonorrhea.

c. Staphylococcus aureus.

d. Chlamydia trachomatis.

 e. b and d

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. a, c, and d

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. a, b, and c

E.

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.

Hexachlorophene has been particularly effective against

a. Staphylococcus aureus.

b. Micrococcus aureus.

c. Escherichia coli.

d. Enterobacter aerogenes.

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. a and b

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

Generally, membrane filters are not used to remove a. bacteria from liquids.

b. microorganisms from gases.

c. spoilage agents from alcoholic beverages.

d. enzymes.

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.

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. is directly absorbed by the organism’s DNA.

Which would be most effective against Pseudomonas?

a. alcohol

b. radiation

c. quaternary ammonium compounds

d. iodophors

Ultraviolet radiation at the bactericidal wavelength destroy bacteria by

a. destroying endospores.

b. damaging nucleic acid.

c. preventing spore formation.

d. denaturing proteins.

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 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.

51. elimination of most pathogens on a

a. sterilization

b. disinfection

c. pasteurization

d. sanitation

e. antiseptic organisms material

52. for use on skin

a. sterilization

b. disinfection

c. pasteurization

d. sanitation

e. antiseptic organisms

53. reduction of microorganisms to meet health standards

a. sterilization

b. disinfection

c. pasteurization

d. sanitation

e. antiseptic organisms

54. use of heat to eliminate pathogens/spoilage organisms

a. sterilization

b. disinfection

c. pasteurization

d. sanitation

e. antiseptic organisms

55. removal of all

a. sterilization

b. disinfection

c. pasteurization

d. sanitation

e. antiseptic organisms

Prions and viroids are easily destroyed by common sterilization procedures.

Organic acids, such as benzoic acid, are often added to foods to prevent microbial growth.