The EMB (Eosin Methylene Blue) agar is a selective and differential agar medium. It contains sucrose and lactose as fermentable substrates together with Eosin Y and methylene blue dyes which in combination gives the agar its characteristic color when prepared and serves as a pH indicator as well as an inhibitor of growth of Gram-positive bacteria. Hence, it is primarily used to isolate Gram-negative fecal coliforms while some positive fecal coliforms such as Staphylococci are also able to grow.
These coliforms are of two types:
- Lactose or sucrose fermenting coliforms form metallic sheens on the agar as a result of acid production and the response of the indicator to the increased acidity.
- Non-lactose/sucrose fermenters are only able to produce acid by protein deamination. Hence they either form colorless or pinkish colonies on the agar
On the other hand, Mannitol salt agar is a selective and differential agar medium that is primarily used to isolate Staphylococcal bacteria. The presence of sodium chloride in the medium makes it a partial or complete inhibitor of other bacteria.
Hence, an unknown bacterium that forms colorless colonies on EMB will either be a non-lactose fermenting, Gram-negative coliform that will hardly grow on Mannitol salt agar, or a Gram-positive fecal Staphylococcus.
Staphylococci bacteria are of two types:
- Coagulase-positive will form yellow colonies on the Mannitol salt agar.
- Coagulase-negative will form red colonies on the Mannitol salt agar.
More about isolating media can be found here: https://brainly.in/question/7238948
Answer:
Protists are a diverse collection of organisms that do not fit into animal, plant, bacteria or fungi groups. While exceptions exist, they are primarily microscopic and made up of a single cell (unicellular), according to the educational website CK-12.
Answer; All the above
A) an atom seeks to fill its outer shell of electrons
B) an atom seeks to balance its positive and negative charges
C) the reaction will result in paired electrons
Explanation;
-In a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.
-During a chemical reaction an atom may lose of gain electrons resulting positive and negative ions (ionic bond formation) or may result to the paired electrons (sharing of electrons).
Answer:
After Cytokinesis, the cells return to Interphase
The skin is made up of three layers, each with its own important parts. The layer on the outside is called the epidermis
