Lab Exam 1

Question 1

Why heat fixing the slide is necessary?

Answer 1

1. Prepare the smear

Question 2

What is the aseptic technique?

Answer 2

No contamination

Question 3

Lawn of bacteria on an agar plate means that the bacteria are _____

Answer 3

The appearance of bacteria growth when testing antibiotics

Question 4

Name one genus of acid fast bacteria

Answer 4

Mycobacterium

Question 5

Bacteria susceptible to an antibiotic means

Answer 5

(Sensitive)affected by antibiotics

Question 6

Is Gram stain a differential stain

Answer 6

Yes

Question 7

Why streaking technique is used?

Answer 7

Steps

Question 8

Colonies inside the zone of inhibition means they are ____ to antibiotics

Answer 8

Resistant

Question 9

Name one spore producing bacteria

Answer 9

Archeaea

Question 10

Spore are called A cells, while growing bacteria are called B cells

Answer 10

A cells

B cells

Question 11

You are given Bibulous paper, Bunsen burner and striker, Crystal violet, Distilled water, Gram’s decolorizer, Immersion oil, Iodine, Lens paper, Loop, tray, three cultures of bacteria.

1. Write down wall steps of gram staining technique, from preparing the slide to looking under the microscope.
2. How can you tell the bacteria is Gram positive or gram negative?
3. Why do you use decolorizing agent in gram staining
4. Name one Gram Positive and one Gram negative bacteria
5. Why do you use oil while looking at your slide under microscope, and what magnification do you oil?

Answer 11

Use oil on 100X magnification