Lab Practical Exam 1 (all the quizzes)

Question 1

when using the 100x objective you should only use the ____ to make the image clearer.
A. coarse focus knob
B. condenser knob
C. fine focus knob
D. Iris diaphragm lever

Answer 1

fine focus knob

Question 2

to increase resolution, we can add a drop of ____ to the slide.
A. 70% ethanol
B. immersion oil
C. mineral oil
D. water

Answer 2

immersion oil

Question 3

what is NOT an example of a structural stain?
A. flagellar stain
B. capsule stain
C. endospore stain
D. simple stain

Answer 3

simple stain

Question 4

gram staining works based on the difference of ___ between Gram negative and Gram positive cells
A. the DNA
B. the cell membrane
C. the cell wall
D. the capsule

Answer 4

the cell wall

Question 5

which is the correct sequence of Gram staining procedure?
A. Crystal violet, iodine, decolorizer, safranin
B. iodine, crystal violet, decolorizer, safranin
C. crystal violet, safranin, decolorizer, iodine
D. safranin, iodine, decolorizer, crystal violet

Answer 5

crystal violet, iodine, decolorizer, safranin

Question 6

what does “S” stand for in “SAM-(EMC)?”

Answer 6

Shape

Question 7

what should NOT be done during a wet mount?
A. put a coverslip on slide
B. use 5 drops of water from source
C. draw organism
D. observe slide at 400x magnification

Answer 7

use 5 drops of water from source

Question 8

a single cell or bacterium when duplicated enough can form a visible___.
A. streak
B. species
C. clump
D. colony

Answer 8

colony

Question 9

using a wet mount with 100x total magnification, which group of organisms will we NOT be able to determine motility?
A. amoebozoa
B. protozoa
C. ciliophora
D. bacteria

Answer 9

bacteria

Question 10

eukaryotes include all the following EXCEPT:
A. bacteria
B. amoebozoa
C. fungi
D. excavata

Answer 10

bacteria

Question 11

where will you place your bacterial plates at the end of today’s class?
A. class bin for incubation at 37 degrees Celsius
B. biohazard bin
C. cardboard box for storage at 4 degrees Celsius
D. back on the bench for growth at room temperature

Answer 11

class bin for incubation at 37 degrees Celsius

Question 12

all the following are true about prokaryotes EXCEPT:
A. have NO nuclear membrane
B. contain a true nucleus
C. are submicroscopic
D. lack sterols

Answer 12

contain a true nucleus

Question 13

Titer = ?

Answer 13

N/DF*V

Question 14

Which one is NOT an important factor in titer?
A. size of tube
B. number of colonies
C. volume
D. dilution factor

Answer 14

size of tube

Question 15

in the titer equation, DF stands for…

Answer 15

the dilution factor

Question 16

the liquid portion of the sample is called:
A. pellet
B. titer
C. dilution
D. supernatant

Answer 16

supernatant

Question 17

in lab 2 of this exercise, you will count the number of colonies on your plates. which is the countable range of colonies you will be looking for?

Answer 17

30-300 CFU

Question 18

how can we avoid a bacterial lawn when we perform a plate count?
A. perform serial dilution
B. sterilize the surface of an agar plate with 70% ethanol
C. incubate the plate at a low temperature
D. add herbicide to the agar side

Answer 18

perform serial dilution

Question 19

MSA stands for:

Answer 19

Mannitol Salt Agar

Question 20

___ might be added to selective media.
A. specific inhibitors
B. salt
C. antibiotics
D. dyes
E. all of above

Answer 20

all of above

Question 21

the rich broth in the fluid thioglycollate is used for:
A. indicating oxygen
B. preventing contamination of the media
C. providing nutrients
D. minimizing oxygen diffusion rates

Answer 21

providing nutrients

Question 22

while putting your needle in the Fluid Thioglycollate soft agar, you should:

Answer 22

keep needle straight while inserting it and removing it from the tube

Question 23

gas production may be seen in which biochemical test?
A. MR-VP test
B. sugar fermentation tube
C. simmon’s citrate
D. MacConkey agar

Answer 23

sugar fermentation tube

Question 24

in Bio221, what technique do you use to inoculate the simmon’s citrate test?
A. needle stab
B. spread plate
C. needle stabe streak
D. loop inoculation

Answer 24

needle stab streak

Question 25

why is it important to use cultures that are 24-36 hours old for detecting catalase? A. these cultures are metabolically inactive and easier to be tested B. fresh cultures do not have catalase C. these cultures are turbid enough, making the change of color easy to recognize D. these cultures are metabolically active and more likely to produce catalase

Answer 25

these cultures are metabolically active and more likely to produce catalase

Question 26

which of following enzymes can convert hydrogen peroxide into water and oxygen? A. catalase B. tryptophanase C. deaminase D. oxidase

Answer 26

catalase

Question 27

the Phenylalanine Deaminase Test uses the indicator: ____, and a positive result turns ___.

Answer 27

ferric chloride; green

Question 28

which of following descriptions is correct? A. lipases are responsible for making lipids B. amylases break down starch to sugars C. helicases unravel the DNA helix D. both amylases break down starch and helicases unravel the DNA helix

Answer 28

both amylases break down starch and helicases unravel the DNA helix

Question 29

when you are finished with the swab at the end of Lab 1 for Enzyme Reactions, where will you place it?

Answer 29

biohazard bin

Question 30

for lab 2 of Enzyme reactions, you should record all of the following EXCEPT: A. organism name B. number of colonies C. growth D. color

Answer 30

number of colonies

Question 31

from what environmental source will we be extracting spores from? A. hand swabs B. water C. soil D. drainpipes

Answer 31

soil

Question 32

what is NOT a stage of biofilm development? A. active dilution B. maturation C. non-reversible attachment D. reversible attachment

Answer 32

active dilution

Question 33

active dispersal of the entrapped cells typically occurs when... A. a disinfectant is used B. the surrounding environment becomes more favorable C. the cell membrane is destroyed D. there is an increase in production of cell structures

Answer 33

the surrounding environment becomes more favorable

Question 34

in the process of cytosine deamination, cytosine is converted to: A. thymine B. adenine C. guanine D. uracil

Answer 34

uracil

Question 35

antiseptics are used on ____ while disinfectants are used on ___. A. living surfaces, living surfaces B. non-living surfaces, living surfaces C. living surfaces, non-living surfaces D. non-living surfaces, non-living surfaces

Answer 35

living surfaces, non-living surfaces

Question 36

in the maturation stage of a biofilm, bacteria lose their.... A. cell wall B. flagella C. capsule D. glycocalyx

Answer 36

flagella