Microbiology Quiz Questions
What is the maximum number of colonies on a plate considered "countable"? (answer with a number)
300
Before doing an experiment, which of the following are done? Select one or more: a. Put on gloves b. Tie back loose hair c. Put on safety glasses d. Wash bench top with disinfectant
All
Before you leave the lab, which of the following are done? Select one or more: a. Return materials neatly to the storage drawers b. Discard used plates in the white biohazard trash can c. Wash bench top with disinfectant d. Turn off Bunsen burners e. Wash your hands f. Remove labels from glass tubes you place in the discard tubs under the cart
All
More than one colony morphology is present on a streak plate you made from a broth in class. Which of the following scenarios could explain this? (More than one scenario may be correct). Select one or more: a. The broth is not a pure broth. b. The broth top was left off for too long. c. The inoculating loop was not flamed properly. d. A contaminant is present.
All
(T/F) All microorganisms used in the BIOL 2051 are BioSafety Level IV pathogens.
False
(T/F) Bacteria have cell walls that prevent them from swelling too much when placed in hypertonic solutions.
False
(T/F) Cell phones are allowed on the bench tops as long as you don't touch them during experiments.
False
(T/F) For experiment 7A, you will inoculate five tubes of nutrient broth with 100microliters of the same organism then place all the tubes at the same temperature.
False
(T/F) Gloves can be worn during the entire lab, even when touching "clean" surfaces like the doorknob to the incubator room or the faucet.
False
(T/F) Heat fixation is only necessary when preparing a smear of non-pathogenic bacteria.
False
(T/F) Immersion oil which is placed between the specimen and the objective increases magnification.
False
(T/F) Microscope slides do not make good surfaces for biofilm formation.
False
(T/F) Motility test medium is a slant.
False
(T/F)After inoculating quadrant 1 of the plate, flame the loop, wait for the loop to cool, obtain more bacteria from the broth, and then inoculate quadrant 2.
False
Escherichia coli is placed in a 15% NaCl solution. The net flow of water is _______
Out of the cell
All microbes have a ______ of temperatures over which they grow.
Range
(T/F) A UV sensitive organism will not be able to survive exposure to ultraviolet radiation for a lengthy period of time.
True
(T/F) A clear area in which there is no bacterial growth around an antibiotic is known as a zone of inhbition.
True
(T/F) A smear is the first step in making a simple stain.
True
(T/F) Actively dividing microorganisms are the most sensitive to antimicrobial chemical agents.
True
(T/F) After viewing a prepared slide of stained flagellated bacteria, you must clean off the coverslip with lens paper and microscope cleaner.
True
(T/F) At higher than the maximum temperature for an organism, cell structure is destroyed, cellular functions cease and cells die.
True
(T/F) Broken glass and slides are discarded in the red plastic biohazard box.
True
(T/F) Calcium is complexed with dipicolinic acid in the core of endospores.
True
(T/F) Growth on the uncovered side of the plate is evidence the organism can survive UV exposure.
True
(T/F) If you swab your plate with Pseudomonas fluorescens you should NOT use the antibiotic dispenser labeled "Gram +" to prevent cross contamination.
True
(T/F) Melted agar is added to the plates after you dispense the dilutions into the sterile Petri dishes.
True
(T/F) Never open a Petri dish which has something furry growing in it, obvious fungal growth.
True
(T/F) Organisms like Vibrio fischeri that live in marine waters are halophiles.
True
(T/F) The disc diffusion method is widely used in clinical microbiology laboratories to determine which antibiotic drugs would be effective for treating an infection.
True
(T/F) The vegetative cell that forms an endospore is genetically identical to the vegetative cell that is formed from that endospore.
True
(T/F) When you calculate population standard deviation, you divide the squared differences by the total number of population observations.
True
(T/F) When you take an isolated colony from a streak plate to streak onto another plate, you are subculturing cells.
True
(T/F) You must put a sterile pipette tip on the end of the pipette before you depress the plunger to the first stop and try to draw up liquid.
True
(T/F)You will be using a PASCO wireless spectrophotometer for the turbidimetric assay.
True
The Gram Stain: Select one: a. Is a differential stain b. Is useful in identifying Gram neutral bacteria c. Stains G+ red and G- purple
a. Is a differential stain
The way an antimicrobial agent works to kill or inhibit microbial growth is referred to as its ____________________________. Select one: a. Mode of action b. Zone of inhibition c. Disc diffusion method d. Miminum inhibitory concentration e. Zone of hydrolysis
a. Mode of action
Which of the following are the correct steps in the procedure for using motility medium to detect motility? Select one or more: a. Obtain 2 motility medium plates per pair b. Stir the motility medium gently with the needle. c. Use a flame sterilized needle to obtain a sample d. Taking care not to hit the bottom, stab the motility deep with the inoculated needle e. Stab into the sample slant to get a sample of Enterobacter aerogenes f. Obtain 2 motility medium deeps per pair g. Carefully scrape the surface of the sample slant
a. Obtain 2 motility medium plates per pair b. Use a flame sterilized needle to obtain a sample d. Taking care not to hit the bottom, stab the motility deep with the inoculated needle f. Obtain 2 motility medium deeps per pair
Streptomycin is the antibiotic produced by Streptomyces griseus and its effective against Gram-positive bacteria. The growth of which bacteria will most likely be affected by Streptomyces grisues? Select one or more: a. Staphylococcus epidermidis b. Bacillus megaterium c. Escherichia coli d. Pseudomonas putida
a. Staphylococcus epidermidis b. Bacillus megaterium
Allergies have been bothering you lately. As you were inoculating your streak plate with E. coli you sneeze. With a plate in one hand and an inoculating loop in the other you were unable to quickly cover your mouth. You tried to sneeze into your arm but your unstifled sneeze was greater than your arm could shield. Following incubation of your plate, what do you expect to see on the plate next lab? Select one or more: a. There will be E. coli along with bacteria from your mouth on the plate. b. Microorganisms are in the air transiently so there could be growth from contaminates in the air. c. Nothing because you did not inoculate the plate. d. Nothing because the media in the plate was sterilized.
a. There will be E. coli along with bacteria from your mouth on the plate. b. Microorganisms are in the air transiently so there could be growth from contaminants in the air.
What does the iodine do in a Gram stain? Select one: a. binds to the primary stain and prevents the stain from leaving the cells with a thick peptidoglycan cell wall b. seals the outside of the cell to prevent the stain from leaving Gram-positive cells c. decolorizes Gram-negative cells d. binds to the counterstain and prevents the stain from leaving the Gram-negative cells
a. binds to the primary stain and prevents the stain from leaving the cells with a thick peptidoglycan cell wall
Onto which surface will you place a drop of Chlamydomonas reinhardtii culture for the hanging drop method? Select one: a. coverslip b. empty Petri dish lid c. depression slide d. stage of the microscope
a. coverslip
Consider the following scenario, then select the dependent variable. You count the number of colony forming units per milliliter in a sample of unpasteurized milk and compare that to an overnight culture of E. coli. You perform 3 counts on the sample of unpasteurized milk and 3 on the culture of E. coli. Select one: a. the number of colony forming units per milliliter b. unpasteurized milk and overnight culture of E. coli
a. the number of colony forming units per milliliter
OIl immersion
allows maximum light rays to pass through
If you take 1mL of your original culture and put it in 99mL of water then take 1mL of that and put it in 9mL of water what is your overall dilution? (Draw it out if it helps) Select one: a. 10^-2 b. 10^-3 c. 10^-4 d. 10^-5 e. None of the above
b. 10^-3
We know that typically all microscopes have eyepiece and objective lenses. But a binocular microscope always has to have ______________ number of eyepieces. Select one: a. Variable b. 2 c. None d. 1 e. 10
b. 2
When you enter lab, which of the following are done? Select one: a. Continue eating the food you just bought at the food truck outside b. Place your cell phone in your backpack for safe storage during lab c. Wash down the food you just ate with a drink d. Place your backpack on the lab bench
b. Place your cell phone in your backpack for safe storage during lab
The stage of biofilm formation where there is the initial adhesion of a few cells to a surface is called Select one: a. development b. attachment c. invasion d. colonization
b. attachment
Which of the following is not needed for the endospore stain? Select one: a. malachite green b. carbolfuchsin c. microscope slide d. clothes pin e. paper square
b. carbolfuchsin
Which of the following terms describes the elevation of a colony? Select one: a. irregular b. flat c. smooth d. round
b. flat
In graphing, you place the ______________________ variable on the X-axis. Select one: a. dependent b. independent
b. independent
When a turf of flagella are attached at one end, the flagella arrangement is called _____________________. When a bacterium has one or more flagella at each end of the cell, the flagella arrangement is called __________________. Select one: a. peritrichous; amphitrichous b. lophotrichous; amphitrichous c. peritrichous; lophotrichous d. amphitrichous; lophotrichous e. monotrichous; peritrichous
b. lophotrichous; amphitrichous
What method of sterilization is used to sterilize the media you use in the lab? Select one: a. filtration b. moist heat sterilization c. electromagnetic radiation d. gas
b. moist heat sterilization
As a benchside group, you will inoculate 5 nutrient broths Select one: a. all pH 11 b. of varying pH. c. all pH 9. d. all pH 7 e. all pH 3
b. of varying pH.
Bacteria in biofilms communicate through Select one: a. cilia b. quorum sensing c. DNA d. lactose e. none of the above
b. quorum sensing
If you made a streak plate from a pure culture, how many different colony morphologies could you expect? Select one: a. 4 b. 2 c. 1 d. 3 e. none
c. 1
You have spilled some Staphylococcus aureus on the countertop.You are worried about what you should do and try to remember what you learned in micro lab.Which of the following make sense and will help you? Select one: a. Bacterial endospores are very resistant to the action of chemical agents. b. Use a paper towel and wear gloves. What's the worst that could happen? c. Antiseptics can be applied to human skin, and are effective in killing pathogenic microorganisms, but you should use a disinfectant d. Cidal agents are lethal to microorganisms. Use a virucide e. Static agents kill microorganisms quickly. They will not continue to grow when the static agent is removed
c. Antiseptics can be applied to human skin, and are effective in killing pathogenic microorganisms, but you should use a disinfectant
What characteristic of cells does the Gram stain differentiate? Select one: a. Cell shape b. Cell arrangement c. Cell wall structure d. Colony shape e. Colony arrangement
c. Cell wall structure
Which of the following organisms will you inoculate onto the preinoculated plate of Penicillium? Select one or more: a. Enterobacter aerogenes b. Pseudomonas fluorescens c. Pseudomonas putida d. Bacillus sphaericus e. Staphylococcus epidermidis f. Staphylococcus aureus g. Escherichia coli h. Bacillus megaterium
c. Pseudomonas putida e. Staphylococcus epidermidis h. Bacillus megaterium g. Escherichia coli
Purple and white would describe the pigmentation of ______________________. Select one: a. Escherichia coli b. Micrococcus luteus c. Streptomyces coelicolor d. Bacillus cereus
c. Streptomyces coelicolor
The symbiotic relationship between two organisms in which there is inhibition, injury or killing of one organism by the other is called Select one: a. antiseptic b. antimicrobial c. antibiosis d. antibiotic
c. antibiosis
Endospores may be located in a _______________ position. Select one: a. external b. terminated c. central d. subteranean
c. central
If you spill live culture on the bench top, Select one or more: a. wipe it clean with your sleeve b. discard the clean materials in the regular trash c. let others nearby and the TA know d. use a disinfectant like vesphene and paper towels to clean up the spill
c. let others nearby and the TA know d. use a disinfectant like vesphene and paper towels to clean up the spill
What type of media will you be using for the osmotic pressure experiment? Select one: a. plates with 0.5%, 5%, 10% and 25% sugar b. plates with 0.5%, 5%, 10% and 25% lipids c. plates with 0.5%, 5%, 10% and 25% NaCl d. plates with 0.5%, 5%, 10% and 25% agar e. both c and d
c. plates with 0.5%, 5%, 10% and 25% NaCl
Condenser
collects and concentrates light
What is the name of the part of the microscope that collects and concentrates light onto the object on the stage?
condenser
It is important to use proper aseptic technique when performing experiments so that you do not introduce ___________ from your hands or the air which could alter the results.
contaminants
What is the total magnification of a compound microscope that has a 50X objective lens and 20X oculars? Select one: a. 70x b. 700x c. 100x d. 1000x e. None of the above
d. 1000x
A smear can be made from Select one: a. Bacteria growing on a solid medium b. A broth culture c. A colony on a plate d. All of the above
d. All of the above
Which of the following are practical reasons for quantifying microbial cell numbers? Select one: a. Determining beverage quality b. Analyzing food products c. Evaluating antibiotics d. All of these choices
d. All of these choices
How will you prepare your plates to test the sensitivity of Pseudomonas fluorescens to various antibiotics? Select one: a. Pour plates b. Swabbing small areas of the plates c. Streak plates d. By covering the entire surface to create a lawn of bacteria e. Not applying bacteria to plates at all
d. By covering the entire surface to create a lawn of bacteria
Which of the following must you wear during lab? Select one: a. Sandals b. Backpack c. Sunglasses d. Gloves
d. Gloves
Analogous to temperature, an organism has a pH________________ at which it grows best. Select one: a. high b. ideal c. acidic d. optimum
d. optimum
What will you use to transfer the antiseptics and disinfectant discs from their storage dishes to your plate? Select one: a. inoculating loop b. inoculating needle c. fingers d. sterile forceps
d. sterile forceps
Which of the following describes how the flagella of Chlamydomonas reinhardtii move? Select one: a. within the cell b. in and out of the cell c. rotate d. whip back and forth
d. whip back and forth
Biofilms are found at Select one: a. water-air interfaces b. water-solid interfaces c. air-solid interfaces d. All of the above e. Answer choices a and b.
e. Answer choices a and b.
What is the prefix used to describe a chain of bacterial cells? Select one: a. Staphylo b. Bacillo c. Vibrio d. Cocco e. Strepto
e. Strepto
If you are given a culture of Thermus aquaticus, a thermophilic bacterium, to conduct experiment 7A, what temperatures do you expect it to survive? Select one: a. only 0 and 4 degrees Celsius b. only 4, 37, 60 and 100 degrees Celsius c. 0 degrees Celsius only d. only 37, 60 and 100 degrees Celsius e. all temperatures
e. all temperatures
Which of the following statements is/are correct? Select one: a. Acidophiles grow well in environments in which the pH is greater than 7. b. Excessive heating kill most organisms because it causes important enzymes to denature and destruction of cellular structures. c. Psychrophiles grow well at low temperature. d. a and b e. b and c f. a, b and c
e. b and c
Which of the following statements is/are NOT correct? Select one: a. Extreme halophiles are organisms that may grow at relatively high salt concentrations, but grow best at low salt concentration. b. If you incubate E. coli at low temperature (e.g. 4 degree Celsius), it will die. c. Mesophiles are organisms that grow well at neutral pH. d. If you placed Bacillus megaterium in boiling water, both the vegetative cells and the endospores will survive. e. Two of the above statements are not correct f. All of the above statements (A, B, C and D) are not correct
f. All of the above statements (A, B, C and D) are not correct
When using the microscope, which of the following statements are true? Select one: a. Focusing with the 10X objective requires oil to be put on the slide. b. You focus on the smear using the 10X objective first using the course adjustment knob. c. After you've focused with the 10X objective, you switch objectives to the 100X objective and use only the fine adjustment knob for focusing. d. You don't have to focus with the 10X objective first if you are careful in using the 100X objective. e. a and b f. b and c g. b and d
f. b and c
Iris diapragm
regulates light
