WorksheetsMetro micro midterm practical
Total questions: 27
Worksheet time: 15mins
0.5 ml is equivalent to how many microliters?
0.005ul
5 ul
50 ul
500 ul
0.05 ul
The micropipette is set at what volume?
2 ul
20 ul
200 ul
2000 ul
Tube 2 is (a) more dilute than the original sample, while tube 3 is (b) more dilute than the original.
You incubate 100 ul of a 10x diluted sample on a TSA plate. You count 45 colonies on the plate. Determine the colony forming units in the original sample.
4,500 cfu/ml
0.45 cfu/ml
450 cfu/ml
0.02 cfu/ml
4.5 cfu/ml
What part of the microscope is indicated in the image?
Ocular lenses
Condenser
Objective lens
Fine knob
What is the total magnification of a microscope with a 10x ocular lens and 40x objective?
4x
0.4x
400x
0.25x
Select all that are correct about the cells in this image.
Gram (+)
Gram (-)
Coccus
Bacillus
Spirillum
During Gram staining, the purpose of the alcohol is to
stain all cells purple
act as a mordant
remove the outer membrane
counter stain the cells pink
remove unbound crystal violet
Acid-fast stains are used to stain
Mycobacterium
Capsules
Flagella
Gram (+)
Gram (-)
Gram staining doesn't work on Mycobacterium because of
the thick peptidoglycan cell wall
the thin peptidoglycan cell wall
the mycolic acid
the capsule
Select the components involved in the acid-fast stain.
Crystal violet
Carbolfuchsin
acid-alcohol
Malachite green
Methylene blue
Which of these is not true about capsules?
Help cells evade the immune system
A positive simple stain is used to visualize them
Should not be heated during staining
Capsule stains stain the background
Select what is true of flagella and staining.
Flagella are used for conjugation
Flagella are smaller than the resolving power of light microscopes
A mordant must be added to make flagella appear larger
Cells are heat-fixed to ensure they are washed away during staining
Select all that are true of endospores and staining.
Are a dormant state that protects the genome from harsh environmental conditions
Stained with Carbolfuchsin
Must be heated during staining
Endospores appear green
Vegetative cells counter stained with methylene blue
An organism that grows best between 20 and 40 C degrees is a mesophile.
True
False
A cell that normally lives in a lake is placed in the ocean. Select all that is true.
Water would rush into the cell
Water would exit the cell
This is a hypertonic environment
This is an isotonic environment
This is a hypotonic environment.
UV light
can penetrate glass
causes thymine dimers
effective on air or surfaces
can penetrate blood
can destroy endospores
The organism growing in this thioglycolate tube is
an aerobe
a facultative anaerobe
an anaerobe
an aerotolerant
a microaerophile
Thioglycolate tubes are used to determine
oxygen requirement
lactose fermentation
glucose fermentation
gas production
indole production
This test indicates
carbohydrate fermentation
no gas production
produces acid through mix-acid fermentation
neutral fermentation products produced
citrate permease is used
The enzyme catalase
converts glucose to an acid
converts citrate into ammonia
converts H2O2 into O2 and H2O
converts tryptophan into indole
After adding Kovac's reagent the positive result indicates the bacterium
utilizes tryptophanase
utilizes citrate permease
is motile
utilizes lactose
produces gas during fermentation
The negative result in this test indicates
no motility
no butylene glycol fermentation
no tryptophanase
no citrate permease
weak lactose fermentation
Select all that are true of this plate.
EMB plate
TSA plate
weak lactose fermenter
strong lactose fermenter
non-lactose fermenter
This tube indicates
Microbe is motile
Microbe produces indole
Microbe is non-motile
Microbe produces cytochrome oxidase
Microbe produces ammonia
Which plate indicates a positive result for fluorescein-producing Pseudomonas species?
A
B
C
D
These results are of
the methyl-red test
the Voges-Proskauer test
the Catalase test
the Cytochrome oxidase test
