Microbiology (Tortora 12th edition) Chapter 6,
7, 10, 11, 12 Test Bank Newest 2026 Questions
and Correct Detailed Answers Already Graded
A+
If cells are grown in media containing amino acids labeled with radioactive
nitrogen (15N), most of the radioactivity will be found in the cells - CORRECT
ANSWER-DNA and proteins.
Nitrogen-fixing bacteria, such as cyanobacteria, can use atmospheric nitrogen
(N2) for their nitrogen source. - CORRECT ANSWER-TRUE
Which of the following is the best method to sterilize heat-labile solutions? -
CORRECT ANSWER-membrane filtration
Which of the following best describes the pattern of microbial death? -
CORRECT ANSWER-The cells in a population die at a constant rate.
Which of the following chemical agents is used for sterilization? - CORRECT
ANSWER-ethylene oxide
,Which of the following substances is used for surgical hand scrubs? - CORRECT
ANSWER-chlorhexidine
Which of the following pairs of terms is mismatched? - CORRECT ANSWER-
bacteriostatic kills vegetative bacterial cells
The antimicrobial activity of chlorine is due to which of the following? -
CORRECT ANSWER-the formation of hypochlorous acid
Which of the following regarding antimicrobial control agents is FALSE? -
CORRECT ANSWER-Alcohols effectively inactivate nonenveloped viruses by
attacking lipids.
Which of the following does NOT achieve sterilization? - CORRECT ANSWER-
pasteurization
9) Which of the following is a limitation of the autoclave? - CORRECT ANSWER-
D) It cannot be used with heat-labile materials.
10) An agent used to reduce the number of bacteria on a toilet would most
accurately be called a(n) - CORRECT ANSWER-A) disinfectant.
,Application of heat to living cells can result in all of the following EXCEPT -
CORRECT ANSWER-decreased thermal death time.
Which of the following disinfectants acts by disrupting the plasma membrane? -
CORRECT ANSWER-bisphenols
Oxidizing agents include all of the following EXCEPT - CORRECT ANSWER-
glutaraldehyde.
Disinfection of water is achieved by all of the following EXCEPT - CORRECT
ANSWER-peracetic acid.
All of the following substances are effective against nonenveloped viruses EXCEPT
- CORRECT ANSWER-alcohol.
Which of the following methods is used to preserve food by slowing the metabolic
processes of foodborne microbes? - CORRECT ANSWER-freezing
Which concentration of ethanol is the most effective bactericide? - CORRECT
ANSWER-70 percent
, All of the following factors contribute to hospital-acquired infections EXCEPT -
CORRECT ANSWER-None of the answers is correct; all of these factors may
contribute to hospital-acquired infection.
Which of the following elements is NOT correctly matched with its cellular
function? - CORRECT ANSWER-phosphorus used for production of
carbohydrates
Pathogenic bacteria isolated from the respiratory or intestinal tracts of humans
are - CORRECT ANSWER-capnophiles that grow best in carbon dioxide
incubators.
The biosafety level (BSL) for most introductory microbiology laboratories is -
CORRECT ANSWER-BSL-1.
The biosafety level (BSL) for a clinical microbiology laboratory working with
potentially airborne pathogens, such as tuberculosis bacteria, is - CORRECT
ANSWER-BSL-3.
A sample of milk is tested for its bacterial content in a plate count assay. A one-
milliliter sample of the milk is diluted in a 1:10 dilution series. One milliliter of the
7, 10, 11, 12 Test Bank Newest 2026 Questions
and Correct Detailed Answers Already Graded
A+
If cells are grown in media containing amino acids labeled with radioactive
nitrogen (15N), most of the radioactivity will be found in the cells - CORRECT
ANSWER-DNA and proteins.
Nitrogen-fixing bacteria, such as cyanobacteria, can use atmospheric nitrogen
(N2) for their nitrogen source. - CORRECT ANSWER-TRUE
Which of the following is the best method to sterilize heat-labile solutions? -
CORRECT ANSWER-membrane filtration
Which of the following best describes the pattern of microbial death? -
CORRECT ANSWER-The cells in a population die at a constant rate.
Which of the following chemical agents is used for sterilization? - CORRECT
ANSWER-ethylene oxide
,Which of the following substances is used for surgical hand scrubs? - CORRECT
ANSWER-chlorhexidine
Which of the following pairs of terms is mismatched? - CORRECT ANSWER-
bacteriostatic kills vegetative bacterial cells
The antimicrobial activity of chlorine is due to which of the following? -
CORRECT ANSWER-the formation of hypochlorous acid
Which of the following regarding antimicrobial control agents is FALSE? -
CORRECT ANSWER-Alcohols effectively inactivate nonenveloped viruses by
attacking lipids.
Which of the following does NOT achieve sterilization? - CORRECT ANSWER-
pasteurization
9) Which of the following is a limitation of the autoclave? - CORRECT ANSWER-
D) It cannot be used with heat-labile materials.
10) An agent used to reduce the number of bacteria on a toilet would most
accurately be called a(n) - CORRECT ANSWER-A) disinfectant.
,Application of heat to living cells can result in all of the following EXCEPT -
CORRECT ANSWER-decreased thermal death time.
Which of the following disinfectants acts by disrupting the plasma membrane? -
CORRECT ANSWER-bisphenols
Oxidizing agents include all of the following EXCEPT - CORRECT ANSWER-
glutaraldehyde.
Disinfection of water is achieved by all of the following EXCEPT - CORRECT
ANSWER-peracetic acid.
All of the following substances are effective against nonenveloped viruses EXCEPT
- CORRECT ANSWER-alcohol.
Which of the following methods is used to preserve food by slowing the metabolic
processes of foodborne microbes? - CORRECT ANSWER-freezing
Which concentration of ethanol is the most effective bactericide? - CORRECT
ANSWER-70 percent
, All of the following factors contribute to hospital-acquired infections EXCEPT -
CORRECT ANSWER-None of the answers is correct; all of these factors may
contribute to hospital-acquired infection.
Which of the following elements is NOT correctly matched with its cellular
function? - CORRECT ANSWER-phosphorus used for production of
carbohydrates
Pathogenic bacteria isolated from the respiratory or intestinal tracts of humans
are - CORRECT ANSWER-capnophiles that grow best in carbon dioxide
incubators.
The biosafety level (BSL) for most introductory microbiology laboratories is -
CORRECT ANSWER-BSL-1.
The biosafety level (BSL) for a clinical microbiology laboratory working with
potentially airborne pathogens, such as tuberculosis bacteria, is - CORRECT
ANSWER-BSL-3.
A sample of milk is tested for its bacterial content in a plate count assay. A one-
milliliter sample of the milk is diluted in a 1:10 dilution series. One milliliter of the
