88. Which of the following statements is not true of filtration? can sterilize heat sensitive liquids
b. a can sterilize provided the pores are exceedingly small c. kills microbes upon contact d. used
in preparation of vaccines, vitamins and drugs special filters can be used to trap microbes in
ventilation systems e. 89. An effective method of sterilizing heat sensitive liquid is: a.
Autoclaving b. UV radiation c. Tyndallization d. Pasteurization e. Filtration 90. Temperature can
control bacteria growth because: a. freezing temperature will kill all bacteria. b. hot temperatures
above 90°C will denature proteins of most vegetative bacteria except extreme thermophiles. c.
Refrigerator temperatures stop the growth of all bacteria d. No bacteria can live above 80 F
TRUE OR FALSE: Mark A for true and B for false on your scantron 91. In general pasteurized
milk is safe and sterile. 92. Ultraviolet radiation is and effective means of sterilization but it is
limited to surfaces 93. All non spore forming bacteria pathogens can be destroyed by heating
them to 94. Alcohols are widely used as antiseptics and disinfectants because that ane 95.
Boiling water for a few minutes is sufficient to render it sterile 96. To sterilize, disinfect, sanitize
and or pasteurize, all mean the same thing. 97. Effective hand washing with bar soap can
eventually sterilize the hands since 175°C for 30 minutes. effectively against endospores as well
as vegetative cells most soaps kill bacteria on contact. Low temperature pasteurization does not
achieve sterility but does kill pathogens present in the product 98.
Solution
Please find the answers below:
Answer 88: Choice c (filtration is a simple process of seiving the microbe from a suspension. It
is a physical process which separates the microbe without killing it)
Answer 89: Choice e (UV-irradiation for 15 minutes is a widely accepted and utilized method for
sterilizing liquids and objects which are heat labile in nature. However, UV irradiation can
degrade some nutrients as well and hence filtration is used)
Answer 90: Choice b (although bacteria are very sensitive to heat, some thermophiles and spore-
bearing bacteria are not killed by heat)
Answer 91: True (pasteurization is a very well established method for sterilization of milk
without deteriorating its nutrients)
b. a can sterilize provided the pores are exceedingly small c. kills microbes upon contact d. used
in preparation of vaccines, vitamins and drugs special filters can be used to trap microbes in
ventilation systems e. 89. An effective method of sterilizing heat sensitive liquid is: a.
Autoclaving b. UV radiation c. Tyndallization d. Pasteurization e. Filtration 90. Temperature can
control bacteria growth because: a. freezing temperature will kill all bacteria. b. hot temperatures
above 90°C will denature proteins of most vegetative bacteria except extreme thermophiles. c.
Refrigerator temperatures stop the growth of all bacteria d. No bacteria can live above 80 F
TRUE OR FALSE: Mark A for true and B for false on your scantron 91. In general pasteurized
milk is safe and sterile. 92. Ultraviolet radiation is and effective means of sterilization but it is
limited to surfaces 93. All non spore forming bacteria pathogens can be destroyed by heating
them to 94. Alcohols are widely used as antiseptics and disinfectants because that ane 95.
Boiling water for a few minutes is sufficient to render it sterile 96. To sterilize, disinfect, sanitize
and or pasteurize, all mean the same thing. 97. Effective hand washing with bar soap can
eventually sterilize the hands since 175°C for 30 minutes. effectively against endospores as well
as vegetative cells most soaps kill bacteria on contact. Low temperature pasteurization does not
achieve sterility but does kill pathogens present in the product 98.
Solution
Please find the answers below:
Answer 88: Choice c (filtration is a simple process of seiving the microbe from a suspension. It
is a physical process which separates the microbe without killing it)
Answer 89: Choice e (UV-irradiation for 15 minutes is a widely accepted and utilized method for
sterilizing liquids and objects which are heat labile in nature. However, UV irradiation can
degrade some nutrients as well and hence filtration is used)
Answer 90: Choice b (although bacteria are very sensitive to heat, some thermophiles and spore-
bearing bacteria are not killed by heat)
Answer 91: True (pasteurization is a very well established method for sterilization of milk
without deteriorating its nutrients)
