Preparing a Smear and Simple Stain Quiz

Question 1

what does the term “smear” mean?

Answer 1

fusing of a microbe to a glass slide

Question 2

are we observing live or dead specimens when viewing a smear slide?

Answer 2

dead microbes

Question 3

what was the first step of preparing a smear?

Answer 3

place two loopfuls of bacteria into target circle, using aseptic technique

Question 4

what was the aseptic technique process we used when preparing the smear?

Answer 4

• opened vile of bacteria, without letting go of the cap
• heated opening of vile in flame before and after collecting specimen
• heated inoculating loop under fire before and after collection of specimen

Question 5

what was the second step of preparing our smear?

Answer 5

air dried smear for 10 minutes

Question 6

what was the third step of preparing our smear?

Answer 6

heat fix the slide by putting slide through flame 6 times

Question 7

what was the purpose of heat fixing the smear?

Answer 7

kills the bacteria
fuses it to the slide

Question 8

what is the purpose of simple staining?

Answer 8

to use one stain to help see morphology of an organism (size and shape)

Question 9

what were the colors of stain we used and what color did they make the specimen?

Answer 9

methylene blue - (blue)
Safranin - (pink)

Question 10

what were the specimens we were able to look at?

Answer 10

Escherichia coli
Staphylococcus aures

Question 11

what shape was Escherichia coli?

Answer 11

bacillus

Question 12

what shape was Staphylococcus aures?

Answer 12

coccus

Question 13

what is helpful physical characteristic that allows endospore to be chemically resistant?

Answer 13

they are encased in a protein coat

Question 14

what physical characteristic allows endospores to be heat resistant?

Answer 14

they lack water

Question 15

during sporulation, the water content of the endospore is reduced how much?

Answer 15

10-30 percent

Question 16

what is responsible for controlling the amount of water coming in and out of the endospore?

Answer 16

cytoplasmic gel

Question 17

what conditions need to be met in order to kill endospores by heat?

Answer 17

must be exposed for 15-20 minutes to steam under pressure, which generates 121 Celsius

Question 18

what is the tool that can be used to kill endospores?

Answer 18

autoclave

Question 19

how would we apply stain to endospores for viewing?

Answer 19

heating endospores before staining

Question 20

What does the Schaeffer-Fulton method of staining endospores include?

Answer 20

using malachite green to stain the endospore (within the cell) and safranin to stain the vegetative portion of the cell (outer portion)

Question 21

what is the process of becoming an endospore called?

Answer 21

sporulation

Question 22

what is the process of an endospore swelling and releasing its vegetative cell called?

Answer 22

germination

Question 23

what are the steps for endospore staining?

Answer 23

1. prepare a smear of Bacillus cereus and allow smear to air dry
2. saturate smear with bibulous paper and malachite green and steam over boiling water for 7 minutes
3. after cooled, remove paper and rinse with water 30 seconds
4. counter-stain with safranin for 30 seconds
5. rinse briefly with water to remove safranin
6. blot dry with bibulous paper, and examine under oil immersion

Question 24

what color will the endospore be after staining?

Answer 24

the vegetative cell will be red and the endospore will be green