Metabolic assays (Lab)

Question 1

What is a starch hydrolysis test used for?

Answer 1

To test for the presence of amylase and starch hydrolysis

Question 2

What is an oxidative fermentation test used for?

Answer 2

To test if the organism is using oxidation or fermentation to metabolize glucose

Question 3

What is a carbohydrate fermentation test used for?

Answer 3

If an organism can use a particular carbohydrate as an energy and carbon source

Question 4

What is a methyl red (MR) test used for?

Answer 4

Tests if an organism is doing mixed acid fermentation

Question 5

What is a Voges-Proskauer test used for?

Answer 5

Tests if an organism is doing butanediol fermentation

Question 6

What is a citrate test used for?

Answer 6

Tests for the presence of citrate lyase and if the organism can use citrate for fermentation

Question 7

What is a KOH test used for?

Answer 7

Confirms if an organism is gram-positive or gram-negative

Question 8

What is an oxidase test used for?

Answer 8

Tests for the presence of cytochrome C

Question 9

What is an ONPG test used for?

Answer 9

Tests for the presence of beta-galactosidase and lactose breakdown

Question 10

What is an indole test used for?

Answer 10

Tests for the presence of tryptophanase and indole production

Question 11

What is MacConkey agar used for?

Answer 11

Selects for enteric gram-negative bacteria and differentiates them based on lactose fermentation

Question 12

What is EMB agar used for?

Answer 12

Selects for gram-negative bacteria and differentiates them based on fermentation type

Question 13

What is a catalase test used for?

Answer 13

Detects the presence of catalase to differentiate between the Micrococcaceae and the Streptococcaceae

Question 14

What is a nitrate reduction test used for?

Answer 14

Tests for the ability of an organism to do nitrate reduction

Question 15

What is blood agar used for?

Answer 15

Used to grow fastidious microbes and tests for hemolysis and the production of hemolysins

Question 16

What is mannitol salt agar used for?

Answer 16

Selects for organisms capable of tolerating high salt conditions and differentiates them based on mannitol fermentation

Question 17

What are the reagents used in a starch hydrolysis test? (2)

Answer 17

1. Nutrient agar + starch

2. Iodine

Question 18

What are the reagents used in an oxidative fermentation test? (4)

Answer 18

1. Bromothymol blue
2. Glucose
3. Peptone
4. Mineral oil

Question 19

What are the reagents used in a carbohydrate fermentation test? (4)

Answer 19

1. Durham tube
2. Carbohydrate of interest
3. Phenol red
4. Peptone

Question 20

What are the reagents used in a methyl red test? (2)

Answer 20

1. Methyl red

2. Nutrient broth

Question 21

What are the reagents used in a Voges-Proskauer test? (3)

Answer 21

1. Nutrient broth
2. KOH
3. Alpha-naphtol

Question 22

What are the reagents used in a citrate test? (3)

Answer 22

1. Sodium citrate
2. Agar
3. Bromothymol blue

Question 23

What are the reagents used in a KOH test? (1)

Answer 23

KOH

Question 24

What are the reagents used in an oxidase test? (1)

Answer 24

ADMA oxalate

Question 25

What are the reagents used in an ONPG test? (1)

Answer 25

ONPG

Question 26

What are the reagents used in an indole test? (3)

Answer 26

1. Kovac's reagent 2. Nutrient broth containing no glucose and with added Trp 3. DMAB

Question 27

What does MacConkey agar contain? (5)

Answer 27

1. Bile salts 2. Neutral red 3. Crystal violet 4. Lactose 5. Peptone

Question 28

What does EMB agar contain? (4)

Answer 28

1. Eosin 2. Methylene blue 3. Peptone 4. Lactose

Question 29

What are the reagents used in a catalase test? (1)

Answer 29

H2O2

Question 30

What are the reagents used in a nitrate reduction test? (5)

Answer 30

1. Nitrate broth 2. alpha-naphylamine 3. zinc powder 4. sulfanillic acid 5. Durham tube

Question 31

What does blood agar contain?

Answer 31

1. Sheep's blood 2. NaCl 3. Nutrient agar

Question 32

What does mannitol salt agar contain?

Answer 32

1. Mannitol 2. NaCl 3. Peptone 4. Phenol red