©NINJANERD 2024/2025. YEAR PUBLISHED 2024.
BMS 602 Exam 3 Questions and
Answers 100% Solved | Graded A+
Which organism does MacConkey agar select for, and how does it work? **
- ✔✔MacConkey is a selective and differential media, that is selective for
species of Enterobacteriaceae.
* This agar will differentiate between Enterobacteriaeceae based on their
ability to ferment lactose.
MAC inhibits growth of : GRAM POSITIVE organisms through the use of
bile salts and crystal violet.
If an organism ferments lactose (E. coli), the colony pH will drop below 6.8,
and turn pink or red. If an organism does not ferment lactose, the colonies
will remain white/colorless.
Which organisms are TSI slants differential for? How does it work? -
✔✔TSI (triple sugar iron) agar differentiates between species of
, ©NINJANERD 2024/2025. YEAR PUBLISHED 2024.
Enterobacteriaceae on their ability to reduce sulfur and ferment
carbohydrates.
This agar contains:
lactose
sucrose
a small amount of glucose
ferrous sulfate
the pH indicator phenol red
If an organism can ferment any of the sugars present, the medium will turn
yellow. Gas production will collect in the bottom of the tube and push the
agar up. (E. coli ferments all three and produces sulfide gas)
GLUCOSE FERMENTERS: red top, yellow bottom
SULFUR REDUCERS: iron sulfide appears as black precipitate, sometimes
obscures results.
** See slides for specific TSI slant results.
List the results of inocculation on a TSI slant for the following organisms:
*** - ✔✔
BMS 602 Exam 3 Questions and
Answers 100% Solved | Graded A+
Which organism does MacConkey agar select for, and how does it work? **
- ✔✔MacConkey is a selective and differential media, that is selective for
species of Enterobacteriaceae.
* This agar will differentiate between Enterobacteriaeceae based on their
ability to ferment lactose.
MAC inhibits growth of : GRAM POSITIVE organisms through the use of
bile salts and crystal violet.
If an organism ferments lactose (E. coli), the colony pH will drop below 6.8,
and turn pink or red. If an organism does not ferment lactose, the colonies
will remain white/colorless.
Which organisms are TSI slants differential for? How does it work? -
✔✔TSI (triple sugar iron) agar differentiates between species of
, ©NINJANERD 2024/2025. YEAR PUBLISHED 2024.
Enterobacteriaceae on their ability to reduce sulfur and ferment
carbohydrates.
This agar contains:
lactose
sucrose
a small amount of glucose
ferrous sulfate
the pH indicator phenol red
If an organism can ferment any of the sugars present, the medium will turn
yellow. Gas production will collect in the bottom of the tube and push the
agar up. (E. coli ferments all three and produces sulfide gas)
GLUCOSE FERMENTERS: red top, yellow bottom
SULFUR REDUCERS: iron sulfide appears as black precipitate, sometimes
obscures results.
** See slides for specific TSI slant results.
List the results of inocculation on a TSI slant for the following organisms:
*** - ✔✔
