BIOL 319 Lecture Notes - Lecture 13: Thermal Death Time, Disinfectant, Antimicrobial Resistance

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greenfly749

20 Apr 2017

School

Binghamton University

Department

Biology

Course

BIOL 319

Professor

Claudia Marques

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Document Summary

Terms: sterilization: process which all living cells, spores, and viruses are destroyed on an object, disinfection: killing or removal of disease producing organisms from inanimate surfaces. Not all organisms are removed: antisepsis: similar to disinfection but applies to removing pathogens from the surface of living tissues, such as skin. Better than sanitation: sanitation: consists of reducing microbial population to safe levels by cleaning an object, as well as. Factors that influence the speed lethal damage occurs. Initial population size: population composition (ex. spores, concentration or dose of agent, duration of exposure, presence of organic material that can inhibit disinfectant action. We want to see whether we have at least 1 log killing, meaning 90% of the population is dead. It all depends on how many bacteria to begin with (ex. (cid:498)kills 99% of bacteria(cid:499) is (cid:883)(cid:882)log(cid:884), Takes around 103 cells before new things don"t which actually not that much if you have a grow.

Related Questions

31. What is the length of time required for a chemical agent (or condition) to kill 90% of a microbial population?

(A) death time (B) partial sterilization time

(C)killing period (D)decimal reduction time

(E) sanitation time

32. The process by which allliving cells, spores, and viruses are destroyed on an object is called

(A) sterilization. (B) disinfection.

(C)antisepsis. (D)sanitation.

(E) all of the above

33. Some endospores can survive an autoclave treatment. Based on the conditions of an autoclave, endospores are _____ and ____ compared to their vegetative cell counterparts.

(A) barophilic / psychrophilic (B) acidophilic / mesophilic

(C)halophilic / barotolerant (D)alkaliphilic / aerotolerant

(E) barotolerant / thermophilic

34. A woman with digestive problems attempts to restore normal gut microflora by ingesting yogurt containing live, active cultures. This is an example of using

(A) antibiotics. (B) probiotics.

(C)phage therapy. (D)bioremediation.

(E) disinfectants.

35. What is the relationship between osmolarity and water activity?

(A) There is a negative correlation; as osmolarity increases water activity also increases.

(B) There is a positive correlation; as osmolarity increases water activity decreases.

(C)There is no correlation between osmolarity and water activity.

(D)There is a negative correlation; as osmolarity increases water activity decreases.

(E) There is a positive correlation; as osmolarity increases water activity also increases.

36. Which of the following enzymes generates hydrogen peroxide when destroying a reactive oxygen species?

(A) superoxide dismutase (B) catalase

(C)peroxidase (D)ATP synthetase

(E) NADH dehydrogenase

37. A genetic program leading to the production of chaperones, proteases, and enzymes that change membrane lipid composition, in response to adverse environmental conditions, is known as the

(A) irradiation response. (B) high pressure response.

(C)halophilic response. (D)Arrhenius response.

(E) heat shock response.

38. Changes in environmental temperature may

(A) affect the fluidity of bacterial membranes.

(B) affect the motion of macromolecules within the bacterial cell.

(C)affect the stability of molecules within bacteria.

(D)all of the above.

(E) none of the above.

39. Within temperatures allowable for growth, higher temperatures usually lead to

(A) higher growth rates. (B) slower growth rates.

(C)no effect on growth rates. (D)unpredictable growth rates.

(E) variable effect, depending on the species.

40. Which of the following sentences is correct?

(A) Sanitation kills all cells, spores, and viruses on an object, sterilization removes pathogens from inanimate surfaces, and disinfection removes pathogens from the surface of living tissues.

(B) Disinfection kills all cells, spores, and viruses on an object, antisepsis removes pathogens from inanimate surfaces, and sterilization removes pathogens from the surface of living tissues.

(C)Sterilization kills all cells, spores, and viruses on an object, disinfection removes pathogens from inanimate surfaces, and antisepsis removes pathogens from the surface of living tissues.

(D)Disinfection kills all cells, spores, and viruses on an object, sterilization removes pathogens from inanimate surfaces, and antisepsis removes pathogens from the surface of living tissues.

(E) Sanitation kills all cells, spores, and viruses on an object, sterilization removes pathogens from inanimate surfaces, and antisepsis removes pathogens from the surface of living tissues.