oxygen requirements

Question 1

what is the thioglycollate broth composed of ?

Answer 1

small amounts of agar, redox indicator, and sodium thioglycollate.

Question 2

why is there only small amounts of agar in the thioglycollate broth?

Answer 2

to limit diffusion

Question 3

what does a redox indicator do?

Answer 3

reveals oxygen rich areas, shows as pink

Question 4

what does the sodium thioglycollate do in thioglycollate broths?

Answer 4

reduces O2 to H2O

Question 5

what are the two types of thioglycollate broths we will see in lab?

Answer 5

facultative anaerobes and areobes

Question 6

facultative anaerobes

Answer 6

prefer to live in O2 enviorments but can live without it.
(moslty growth on top but a few throughout)

Question 7

obligate/ strict anaerobes

Answer 7

Dont use O2 and CANNOT live in it
(all growth towards the bottom)

Question 8

aerobes

Answer 8

require oxygen for metabolism
(growth all on top)

Question 9

aerotolerant

Answer 9

Dont use O2 in metabolism and CAN be in its presence
(growth is evenly distributed)

Question 10

microaerophiles

Answer 10

2-10% O2

Question 11

what are the examples of monosaccharides?

Answer 11

glucose, galactose, mannose

Question 12

what are the examples of Disaccharides?

Answer 12

sucrose, lactose, maltose

Question 13

what is the polysaccharide?

Answer 13

starch

Question 14

what does phenol red broth tubes use as an indicator?

Answer 14

red pH indicator

Question 15

when using the phenol red broth tubes, what is the test looking for? what color does the broth turn?

Answer 15

acid production, yellow coloration

Question 16

what tube is used to test the carbohydrates? what does it do?

Answer 16

durham tube, detects CO2 production

Question 17

in the TSI agar slants, what percent of acid production in glucose, lacotse and sucrose is there?

Answer 17

glucose: 0.1%
lactose and sucrose: 1%

Question 18

what is another name for the triple sugar iron slants?

Answer 18

kligler slants

Question 19

if glucose is used only the _____ of the tube will turn _______?

Answer 19

butt, yellow

Question 20

T/F in TSI slants, If lactose and/or sucrose is used then both the butt and the slants will turn yellow?

Answer 20

T

Question 21

how do you know if there is CO2 production in the triple sugar iron slants?

Answer 21

if there are cracks or lifting of the agar

Question 22

what does the iron do in the TSI slants?

Answer 22

gives the organism the ability to express thiosulfate reductase

Question 23

what is thiosulfate reductase used in?

Answer 23

used in sulfer reduction

Question 24

in the TSI, what is produced from thiosulfate?

Answer 24

H2S

Question 25

In TSI, whats helps produce the black precipitate?

Answer 25

ferrous ammonium sulfate

Question 26

when using a starch there are many glucose units that are too large to get through the membrane, what enzyme is used to break it down? where is it secreted?

Answer 26

amylase, secreted outside (exoenzyme)

Question 27

when using the starch plates, after you pour the iodine how long do you incubate for?

Answer 27

1 minute

Question 28

When using starch plates, after the iodine is poured off, what does it mean when the plate is brown all over? what does it mean when there is a zone of clearing around the bacteria?

Answer 28

brown all over = has starch
zone of clearing= no starch

Question 29

What is motility, and what percent agar is used?

Answer 29

the use of semisold agar, (0.8% agar)

Question 30

When testing motility how does the 2,3,5 triphenyltetrazolium (TTC) work?

Answer 30

its colorless, but as the organism grows the dye will be incorperated in the bacteria and reduced to a red insoluable pigment.

Question 31

What is the process of 2,3,5 triphenyltetrazolium (TTC) working in the motility test called?

Answer 31

formazan

Question 32

when testing motility, what is added to see the results?

Answer 32

2,3,5 triphenyltetrazolium (TTC)

Question 33

what are examples of facultative anaerobes

Answer 33

fermentation and anaerobic respiration

Question 34

if you inoculated a semi solid agar that contained triphenyltetrazolium chloride, how would the tube look after incubation with a nonmotile bacterium?

Answer 34

the tube would have a small amount of growth around the inoculated needle insertion with a red insoluble pigment.