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Question 1

What is a complex, selective, and differential medium

Answer 1

Eosin methylene blue agar

Question 2

What contains a digest of gelatin, lactose, and the dues eosin and methylene blue

Answer 2

Eosin methylene blue agar

Question 3

What is the purpose of the two dues in EMB

Answer 3

1) inhibit growth of most gram positive organisms

2) react with lactose fermenters whose acid products turn the growth black

Question 4

What do lactose non fermenters appear like

Answer 4

Retain their normal color or take the coloration of the medium

Question 5

What is EMB agar used for

Answer 5

Isolation of fecal coliforms

Question 6

Fermentation of lactose by the coliform produces what

Answer 6

Shiny green appearance to the growth

Question 7

Poor or no growth in EMB is

Answer 7

Gram positive

Question 8

Good growth on EMB is

Answer 8

Gram negative

Question 9

Growth is pink in EMB

Answer 9

Possible coliform

Question 10

Growth is dark in EMB

Answer 10

Probable coliform

Question 11

Growth is colorless in EMB

Answer 11

Noncoliform

Question 12

What does Columbia CNA do

Answer 12

Allows growth of gram positive organisms and inhibits growth of gram negative organisms

Question 13

What act as selective agents against gram negative organisms in Columbia CNA

Answer 13

Antibiotics colistin and nalidixic acid

Question 14

What does the sheep blood part of Columbia CNA do

Answer 14

Differentiation of gram positive organisms based on hemolytic reaction

Question 15

What is Columbia CNA agar used to do

Answer 15

Isolate staphylococci, streptococci, and enterococci

Question 16

What are the only organisms that grow well on the Columbia CNA agar

Answer 16

Gram positive

Question 17

What does the NA plate will serve as what

Answer 17

A comparison for growth quality on the Columbia CNA with 5% sheep blood agar plate

Question 18

Poor or no growth on Columbia CNA

Answer 18

Probable gram negative organism

Question 19

Good growth with clearing of medium in Columbia CNA

Answer 19

B hemolytic

Question 20

Good growth with greening of medium in Columbia CNA

Answer 20

Probable ~ hemolytic

Question 21

Good growth with. No change of medium in Columbia CNA

Answer 21

Probable y hemolytic

Question 22

What does mannitol salt agar contain

Answer 22

The carbohydrate mannitol, 7.5% sodium chloride, and the pH indicator phenol red

Question 23

When is phenol red yellow

Answer 23

Below 6.8

Question 24

When is phenol red red

Answer 24

7.4 to 8.4

Question 25

When is phenol red pink

Answer 25

8.4 and above

Question 26

What does mannitol provide

Answer 26

Substrate for fermentation and makes the medium differential

Question 27

What thrive on mannitol salt agar

Answer 27

Staphylococci

Question 28

What does phenol red indicate

Answer 28

Whether fermentation with an acid end product has occurred

Question 29

What is mannitol salt agar used for

Answer 29

Isolation and differentiation of staphylococcus