TEST BANK For Microbiology: The Human Experience 2nd
Edition By Foster; Aliabadi; Slonczewski Given the incredibly fast division times of bacterial cells, which of the following could explain why we are NOT surrounded by large mountains of bacterial cells? -
ANSWER:Bacteria run out of nitrogen.
A chemically-defined-minimal-medium contains only the most basic compounds an
organism needs to grow and nothing more. - ANSWER:TRUE
If you were trying to isolate a pure culture of Staphylococcus aureus from the skin lesion of an infected individual, you would use appropriate sampling techniques and would specifically have to culture the microorganism onto _agar plate -
ANSWER:TRUE
Fastidious organisms would be best grown on which type of media? -
ANSWER:Enriched
What advantage does the plating method shown on the left panel below have over the plating method shown in the right panel? - ANSWER:It can be used to quantify the number of organisms in a given bacterial sample.Mannitol salts agar is a medium that contains a high concentration of salt (7.5%) and mannitol as a fermentable carbon source. Few organisms are able to grow on it because of its high salt concentration. Organisms that can grow and ferment mannitol will produce an acid that interacts with the pH indicator in the media, turning it yellow. Nonmannitol-fermenting organisms grow without any change to the media. Which of the following correctly describes this medium? -
ANSWER:selective and differential
Which of the following can be most efficiently used to measure bacterial growth in
real time? - ANSWER:spectrophotometer
Which of the following is NOT required for microorganisms to grow and divide? -
ANSWER:conjugation
A culture of Salmonella increases from 20 cells to over 10,000 cells in just three
hours. Of what is this an example? - ANSWER:exponential growth
If you start with 14 organisms at time 0, how many organisms will you have after 9
generations, assuming exponential growth? - ANSWER:7,168
Which of the following is NOT happening during the lag phase of growth? -
ANSWER:Cells are at their largest. 1 / 2
Which of the following occurs when a microorganism is found in an environment
below its minimum growth temperature? - ANSWER:Growth stops because
enzymatic processes become sluggish.What classification is also given to barophilic organisms that grow at the ocean floor?
- ANSWER:psychrophilic
Production of urease by Helicobacter pylori allows it to do which of the following? -
ANSWER:neutralize stomach pH to survive in acidic conditions
Mesophilic proteins are less flexible than psychrophilic proteins. - ANSWER:True Aerobic bacteria are capable of using oxygen as a terminal electron acceptor in the
electron transport chain. - ANSWER:True
Consider the tube shown. What type of organism would grow only at the bottom of
the tube? -5UM Ó (REF. 6.2) - ANSWER:strict anaerobe
Why do strict anaerobes die in the presence of oxygen? - ANSWER:They are
vulnerable to reactive oxygen species.Why might a facultative organism prefer aerobic respiration over fermentation when
carbohydrates become scarce? - ANSWER:It gets more energy from aerobic
respiration.What is the purpose of the palladium packet in the anaerobic jar?REF: 6.5 - ANSWER:to catalyze a reaction between H2 and residual Ó in the jar to remove all the Ó Within aquatic environments, bacteria are mainly found associated with surfaces in
the form of a biofilm - ANSWER:True
The production of antibiotic-resistance mechanisms in a biofilm helps maintain the viability of a biofilm during an infection.
REF: 6.6 - ANSWER:TRUE
Why do bacterial organisms form a biofilm? - ANSWER:to attach to a surface in an area where food is plentiful A young mother who recently emigrated from Uganda brought her sick 18-month- old infant, Mirembe, to a New York City emergency room. The infant was crying uncontrollably, especially when the physician tried to move her head. Meningitis (an infection of the spinal fluid and membrane surrounding the brain) was suspected,
- / 2