Describe what positive and negative test result looks like and what the results mean.

This is an individual activity. Please, open the attached document to complete this assignment.
Select two (2) other differential tests on the document (it cannot be MSA, EMB, nor MacConkey). The tests must be from the document provided here and not from any other website. Following directions and Rubric will ensure that you get a good grade.
Upload a MS Word file, PDF, or Pages file with the following information for each of the 2 chosen media. You can put the information in form of a table or answer/question format
Name of the media and what it is used for.
Label the media as selective, differential, reducing, etc. It can be a combination of some of these.
List the primary ingredients of each media and what the function of each ingredient is in the test.
Describe what positive and negative test result looks like and what the results mean. You can include a photo too.
Please, see attached Rubric
Sample Assignment (Do not use this sample assignment)
1. MSA (Mannitol Salt Agar) is used to test for pathogenic Staphylococcus species of bacteria.
2. MSA is both selective and differential. It will select against non-halophilic bacteria and is differential between species of Staphylococcus.
3. MSA contains the following:
Mannitol- differential ingredient. This is the carbohydrate that is fermented by S. aureus but not some other forms of staph.
Salt- salt is in the media as a selective agent. Only halophilic gram + bacteria are capable of growing in the salt concentration.
Phenol Red: this is the pH indicator used to detect if fermentation is occurring. It will be yellow in acidic conditions and pink in alkaline conditions.
4. An organism that is positive on MSA will ferment the mannitol, causing the pH to drop and the indicator phenol red will turn yellow. So colonies in agar that has turned yellow are positive.
An organism that is negative on an MSA will either not grow at all or it will break down proteins because it cant use the mannitol. The breakdown of proteins will release alkaline conditions causing the phenol red to turn pink.
Organism A is negative, Organism B is positive and Organism C was a gram negative bacteria which cannot grow in MSA.

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