Quiz
Speedback Assignment 2
Crie uma conta grátis para terminar este quiz
Salve seu progresso e veja sua nota final.
Já tem uma conta? Inicie sessão
Perguntas do quiz (30)
1A medium that contains yeast extract, glucose, and peptones would be a(n)
- Acomplex medium
- Bselective medium
- Canaerobic medium
- Dchemically defined medium
2A bacterial suspension produces a turbidity reading that corresponds to 5 x 107 CFU/ml. A viable plate count of the same suspension produces a concentration of only 1 x 105 CFU/ml. You most correctly conclude that
- Ayou forgot to use the 500x multiplier that is always a part of computing viable counts.
- Bturbidity is an indirect counting method and is inherently inaccurate.
- Cmost of the cells in the suspension are dead.
- Dthe suspension is safe to drink.
3In metabolism, ______ reactions liberate energy used to make ATP, whereas ______ reactions require energy supplied by the hydrolysis of ATP.
- Aanabolic, catabolic
- Bcatabolic, anabolic
- Cbiosynthetic, degradative
4The ATP made by oxidative phosphorylation
- Ais powered by chemiosmosis using a proton gradient.
- Bis made at large transmembrane proteins called ATP synthases.
- Crepresents most of the energy made during respiration.
- Dall of the above.
5Why are both the temperatures and times involved in hot air sterilization higher than those involved in steam sterilization?
- AHeat transfer is more efficient when water is involved.
- BDesiccated organisms are harder to kill.
- CMicrobes have more organic material to eat in ovens.
- DMicrobes are hydrophobic.
6At which phase of microbial growth is the growth rate identical to the death rate?
- Alag phase
- Bdeath phase
- Cstationary phase
- Dlog phase
7A bacterial growth experiment began with 100 cells and ended with 409,600 cells. How many generations occurred?
- A3
- B6
- C24
- D12 [Log (409,600) - Log (100)]/log 2=12, See Appendix B
8During Glycolysis
- AATP is generated by substrate-level phosphorylation
- Bcarbon dioxide is produced.
- Coxygen is consumed.
- Dall of the above.
9Suppose you have a suspension of C. botulinum endospores that has a decimal reduction time (DRT) of 1.5 minutes at 121 °C. If you had 1 x 10 6 endospores, how long (at 121 °C ) would it take to reduce this number to a single organism?
- A12 minutes
- B3 minutes
- C9 minutes
- D6 minutes
10The process of destroying vegetative pathogens on living tissue is most correctly called
- Adisinfection.
- Bsanitization.
- Csterilization.
- Dantisepsis.
11What type of organism would have an optimum growth temperature at about 12 °C?
- Apsychrophile
- Bpsychrotroph
- Cthermophile
- Dmesophile
12Plasmas, supercritical fluids, and peroxygens are all
- Aobsolete microbial control methods.
- Bnew methods used to sterilize.
- Cused to grow bacteria.
- Dcommonly used in surgeries.
13The most important products of the Krebs cycle are
- Acitric acid and pyruvic acid.
- BATP and water.
- CNADH and FADH2.
- Dcarbon dioxide and water.
14The method of preserving bacterial cultures that involves sublimation is
- Adrying.
- Bdeep-freezing.
- Clyophilization.
- Drefrigeration.
- Adrying.
15The germicidal action of chlorine is due to the formation of
- Ahypochlorous acid.
- Bsodium chloride.
- Cfree oxygen.
- Dozone.
16The net yield of ATP equivalents from one turn of the Krebs cycle (starting with acetyl-CoA) is
- A12
- B36
- C24
- D6
17The most common physical method of microbial control in foods is
- Aheat treatment or low temperatures.
- Bpressure.
- Cradiation.
- Dfiltration.
18The most resistant microbe (of the ones listed) to chemical biocides is
- Aprotozoan cysts.
- Bmycobacteria.
- Cbacterial endospores.
- Dviruses without envelopes.
19A bacterostatic agent
- Acauses bacteria to grow.
- Bkills bacteria using an electric charge.
- Ckills bacteria.
- Dinhibits the growth of bacteria.
- Acauses bacteria to grow.
20Flavoproteins, cytochromes, and ubiquinones are all part of
- Athe electron transport chain.
- Bthe pentose phosphate pathway
- Cglycolysis.
- Dthe Krebs cycle.
- Athe electron transport chain.
21Phenolics, biguanides, halogens, alcohols, and probably quaternary ammonium compounds (Quats) all cause damage to the cell’s
- Awall
- Bnucleic acids
- Ccapsule
- Dplasma membrane
22 Radiation does most of its lethal damage by causing breaks in, or changes to the microbe’s
- Aplasma membrane.
- Bcell wall
- CDNA
- Dflagella
23Which of the following is not a common end product of a microbial fermentation?
- Aethyl alcohol
- Blactic acid
- Cglucose
- DCO2
24Organisms that grow deep in the bottom of the ocean (no light) next to hydrogen sulfide vents (source of energy), and are able to fix CO2 in the seawater, would be referred to as
- Aphotoheterotrophs.
- Bphotoautotrophs.
- Cchemoautotrophs.
- Dchemoheterotrophs.
25Which type of organism is indifferent to either the presence or absence of oxygen?
- Amircoaerophile
- Bobligate anaerobe
- Cfacultative anaerobe
- Daerotolerant anaerobe
26During photosynthesis, the main products of the light-dependent reactions are ________, whereas the main products of light-independent reactions are __________.
- Achlorophyll/NADPH and O2
- Blipids/proteins
- Csugars/ATP and water
- DATP, O2, and NADPH/sugars
27Enzymes
- Araise the temperature of a chemical reaction.
- Bare permanently altered by a chemical reaction.
- Clower the activation energy of a chemical reaction.
- Dlower the energy difference between the reactants and products.
28Five bacterial cells with a generation time of 15 minutes were allowed to grow for 8 hours. How many cells are present?
- A5 million
- B3.20 × 108
- C4.29 × 109
- D2.15 × 1010
29A sample of milk is diluted 1:2,000,000 and 1 ml samples of this dilution are plated in duplicate. The average plate count is 50 CFU. How many CFU/ml are present in the undiluted milk?
- A50,000,000
- B100,000,000
- C10,000,000
- D500,000,000
30Blood agar containing an antibiotic that inhibits gram-positive organisms, would most correctly be called
- Aselective.
- Banaerobic.
- Cboth selective and differential
- Ddifferential
Informações
- Descrição
- Chapter 5 - Microbial Metabolism Chapter 6 - Microbial Growth Chapter 7 - The Control of Microbial Growth
- Autor
- elizabeth.merner
- Idioma
- English
- Visualizações
- 23
- Etiquetas
- Avaliação
- Ainda sem avaliações Avalie este quiz