MBIO Exam Flashcards
What is Mannitol Salt Agar used for
To test for Halotolerant organisms capable of fermenting Mannitol.
What would a positive test for Mannitol Salt Agar look like
Color change from RED to YELLOW if organism can ferment Mannitol.
What is Alpha Hemolysis
When we see a green hallow around bacterial colonies,
What is Beta Hemolysis
Clear zone around bacterial colony indicating the complete destruction of red blood cells.
What is Gamma Hemolysis
No destruction of red blood cells.
What is MacConkey Agar used for
To selectively grow G-, enteric bacteria capable of fermenting lactose.
What is DNase agar used for
Used to see whether or not the bacteria produces extracellular nucleases which break down DNA.
What is a positive result for DNase agar.
We should see a zone of clearing around the bacterial colonies from the blue-green color.
What is the Positive test for MacConkey Agar
The bacterial colonies themselves would turn purple
What do we see when E.coli ferments lactose on a plate.
E.coli typically would not only be purple but have a purple halo around it.
What is the positive result for the Urea tube
The tube would go from yellow to pink.
Original Color is yellow.
Positive result for the PBB tube.
Turns from purple to yellow indicating that the bacteria does ferment whatever sugar is in the tube.
What does it mean if there is gas in the Durham vial.
That the bacteria ferments the sugar using a pathway that produces glucose.`
Where can we find the coarse and fine focus knobs respectively.
The coarse can be found on both sides, the fine focus can be found only on the right side of the microscope.
What is the starch plate used to test for.
If the bacteria produces the amylase enzyme or not.
