Lab 45-48

Question 0

What is beta Hemolysis

Answer 0

Complete hemolysis, giving a clear zone with a clean edge around the colony

Question 1

What is alpha hemolysis

Answer 1

Green, Claudia zone around the colony. Partial destruction of red blood cells due to bacteria produce hydrogen peroxide

Question 2

What is gamma hemolysis

Answer 2

No hemolysis, and no change in the blood agar around the colony

Question 3

Which bacteria is bile soluable

Answer 3

Streptococcus pneumoniae

Question 4

What is special about MacConkey plates

Answer 4

They only grow (are selective for) gram-negative organisms.

Question 5

How are MacConkey plates differential

Answer 5

Lactose fermenting organisms give read colonies and non-lactose fermenters give translucent colonies.

Question 6

What ingredients are in triple sugar ironed agar

Answer 6

.1% glucose, 1% lactose, 1% sucrose. .02% sulfate, phenyl red, nutrient agar

Question 7

What change happens in a positive citrate test

Answer 7

Turns from green to blue

Question 8

What change happens in a positive glucose lactose or sucrose fermentation test

Answer 8

The solution turns from red to yellow

Question 9

What happens in a positive coagulase test

Answer 9

The solution is clumpy not starry

Question 10

What happens in a positive oxidase test

Answer 10

The smear turns purple

Question 11

What happens in a positive TSI test and how do you know if sulfur is produced

Answer 11

If it ferments it stays yellow. If sulfurs produced the tube turns black

Question 12

What tests are necessary to do in order to identify gram-positive bacteria

Answer 12

Blood agar plate, catalase test, thioglycolate. If positive catalase test then inoculate MSA plate and do a coagulase test.

Question 13

What tests are necessary in order to identify gram-negative bacteria

Answer 13

Oxidase test, MacConkey plate, citrate test, glucose sucrose and lactose fermentation test

Question 14

List all gram-positive bacteria

Answer 14

Staphylococcus aureus,
micrococcus Luteus,
staphylococcus epidermidis, Streptococcus pneumonia, streptococcus pyogenes

Question 15

List all gram-negative bacteria

Answer 15

E. coli, Serratia marcescens, Proteus vulgaris, pseudomonas aeruginosa, E aerogenes.

Question 16

List all test results for Staphylococcus aureus

Answer 16

Gram-positive,
catalase positive,
coagulase positive

Question 17

List all test results for E. coli

Answer 17

Gram-negative, 
citrate negative, 
oxidase negative, 
MacConkey agar positive, 
TSI +/(+), GLS: ferment glucose lactose and sucrose + produces gas with glucose and lactose.

Question 18

List all test results for Serratia marcescens

Answer 18

Gram-negative, 
citrate positive, 
oxidase negative, 
MacConkey agar negative, 
TSI +/+, 
GLS: ferment glucose and sucrose.

Question 19

List all test results for micrococcus Luteus

Answer 19

Gram-positive, 
coagulase negative, 
catalase positive, 
MSA negative, 
BAP negative, 
bile soluble

Question 20

List all test results for staphylococcus epidermidis

Answer 20

Gram-positive, 
catalase positive, 
MSA negative, 
coagulase negative, 
BAP negative

Question 21

List all test results for Proteus Vulgaris

Answer 21

Gram-negative,
 oxidase negative, 
site trait negative, 
MacConkey agar negative, 
TSI +/+ H2S, 
GLS: +,-,+

Question 22

List all test results for pseudomonas aeruginosa

Answer 22

Gram-negative, 
Citrate positive, 
oxidase positive, 
MacConkey negative, 
TSI: -/-
GLS: -,-,-

Question 23

List all test results for streptococcus pneumonia

Answer 23

Gram-positive,
catalase negative,
alpha hemolytic BAP

Question 24

List all test results for E. Aerogenes

Answer 24

Gram-negative, 
oxidase negative, 
Citrate positive, 
Macconkey positive, 
GLS: +g, +g, +
TSI: +/(+)

Question 25

List the test results for streptococcus pyogenes

Answer 25

Gram-positive,
catalase negative
beta hemolytic BAP