©THEBRIGHT EXAM STUDY SOLUTIONS 8/26/2024 11:32 AM
Microbiology (Tortora 12th edition) Chapter 6, 7, 10, 11, 12 test bank. Exam Questions And Correct Answers
If cells are grown in media containing amino acids labeled with radioactive nitrogen (15N), most of the radioactivity will be found in the cells - answer✔✔DNA and proteins.Which of the following elements is NOT correctly matched with its cellular function? - answer✔✔phosphorus used for production of carbohydrates Pathogenic bacteria isolated from the respiratory or intestinal tracts of humans are - answer✔✔capnophiles that grow best in carbon dioxide incubators.The biosafety level (BSL) for most introductory microbiology laboratories is - answer✔✔BSL-1.The biosafety level (BSL) for a clinical microbiology laboratory working with potentially airborne pathogens, such as tuberculosis bacteria, is - 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 third dilution tube is plated in a pour plate. After incubation, the plate has 54 colonies, indicating that the original milk sample contained - answer✔✔54,000 cells per milliliter.The addition of which of the following to a culture medium will neutralize acids? - answer✔✔buffers Salts and sugars work to preserve foods by creating a - answer✔✔hypertonic environment.The term aerotolerant anaerobe refers to an organism that - answer✔✔does not use oxygen but tolerates it.Which of the following is an advantage of the standard plate count? - answer✔✔determines the number of viable cells Which of the following is an advantage of the direct microscopic count? - answer✔✔requires no incubation time 1 / 2
©THEBRIGHT EXAM STUDY SOLUTIONS 8/26/2024 11:32 AM
Most bacteria reproduce by - answer✔✔binary fission.Thirty-six colonies grew in nutrient agar from 1.0 ml of undiluted sample in a standard plate count. How many cells were in the original sample? - answer✔✔36 per milliliter Most bacteria grow best at pH - answer✔✔7 Most fungi grow best at pH - answer✔✔5 Consider a culture medium on which only gram-positive organisms such as Staphylococcus aureus colonies can grow due to an elevated NaCl level. A yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the pH as a result and changing the color of a pH indicator chemical. This type of medium would be referred to as a(n)
- answer✔✔selective and differential medium.
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A culture medium consisting of agar, peptone, and beef heart is a - answer✔✔complex medium Which of the following pairs of microbe classification terms and optimal growth temperatures is mismatched? - answer✔✔thermophile growth at 37C During which growth phase will gram-positive bacteria be most susceptible to penicillin? - answer✔✔log phase Which of the following is the best definition of generation time? - answer✔✔the length of time needed for a cell to divide Which of the following is NOT a direct method to measure microbial growth? - answer✔✔metabolic activity Which group of microorganisms is most likely to spoil a freshwater trout preserved with salt? - answer✔✔facultative halophiles Which of the following is an organic growth factor? - answer✔✔vitamin B1 Which of the following is an example of a metabolic activity that could be used to measure microbial growth? - answer✔✔glucose consumption An experiment began with 4 cells and ended with 128 cells. How many generations did the cells go through? - answer✔✔5 Three cells with generation times of 60 minutes are inoculated into a culture medium. How many cells are there after 5 hours? - answer✔✔96 In one hospital, Pseudomonas aeruginosa serotype 10 infected the biliary tract of 10 percent of 1300 patients who underwent gastrointestinal endoscopic procedures. After each use, endoscopes were washed with an automatic reprocessor that flushed detergent and glutaraldehyde through