Aseptic Technique

Question 1

What should be done before handling the cultures, moving them, or isolating them?

Answer 1

Flame the inoculating loop.

Question 2

How many times should you overlap from Q3 to Q4?

Answer 2

Once

Question 3

What should be done between spreading each quadrant of a streak plate?

Answer 3

Flame the inoculating loop.

Question 4

How do you heat fix a slide?

Answer 4

1. Drop a minute amount of distilled water or saline on the slide.
2. Flame loop.
3. Hold culture plate lid at an angle and obtain a tiny amount of sample.
4. Mix water and sample on the slide.
5. Allow to air dry.
6. Pass slide through flame three times with smear side up.

Question 5

What chemical is used first in Gram staining and for how long?

Answer 5

Crystal violet, let sit for 60 seconds.

Question 6

What chemical is used second in Gram staining and for how long?

Answer 6

Iodine, let sit for one minute

Question 7

What chemical is used third in Gram staining and for how long?

Answer 7

Gram’s alcohol, rinse for 5-10 seconds or until it runs clear.

Question 8

What chemical is used fourth in Gram staining and for how long?

Answer 8

Safranin, 1 - 2 minutes

Question 9

What is the last step of Gram staining?

Answer 9

Blot the slide with kim wipes.

Question 10

What lens is used to observe Gram stains?

Answer 10

Oil immersion

Question 11

What color is a Gram positive cell?

Answer 11

Purple

Question 12

What color is a Gram negative cell

Answer 12

Pink

Question 13

What characteristics are unique to Gram positive cells?

Answer 13

Thick PGL layer

Question 14

What characteristics are unique to Gram negative cells?

Answer 14

Thinner PGL layer, outer membrane, periplasmic space

Question 15

What antibiotics work best on Gram positive bacteria?

Answer 15

Penicillins

Question 16

What antibiotics work on both on Gram positive and negative bacteria?

Answer 16

Ampicillins

Question 17

Define the term colony.

Answer 17

A group of bacteria grown from a single cell.

Question 18

What is done between every step of the Gram stain process?

Answer 18

Rinse with water at a 45 degree angle for two seconds.

Question 19

What are antibiotics?

Answer 19

1. Drugs that destroy bacteria.

2. Drugs that prevent bacterial infection.

Question 20

Two types of antibiotics

Answer 20

1. Bacteriostatic

2. Bactericidal

Question 21

What do bacteriostatic antibiotics do?

Answer 21

Prevents cell division or processes

Question 22

What do bactericidal antibiotics do?

Answer 22

Kill or destroy bacteria directly.

Question 23

When was penicillin discovered?

Answer 23

1928

Question 24

Who discovered penicillin?

Answer 24

Andrew Fleming

Question 25

How do dyes stain the bacteria?

Answer 25

The negatively charged bacterial cytoplasm attracts the positively charged dye.

Question 26

How do the crystal violet and Gram’s iodine interact?

Answer 26

They produce a crystal violet-iodine complex that appear blue.

Question 27

How do Gram negative cells appear pink?

Answer 27

The bacteria is washed with an alcohol decolorized and then dyed pink with Safranin.