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
Calculate the acceleration of a boat that has been cruising
at 15 m/s but speeds up to 45 m/s in about 6 seconds. Don’t forget your units, m/s2.
In order to calculate the acceleration of the boat we first
have to identify the suited formula for acceleration in this scenario.
Hence, a = vf – vi / t.
Vi = 15 m/s
Vf = 45 m/s
T = 6 seconds
Solution:
A = 45 m/s – 15m/s / 6s
A = 5m/s^2
Answer:
where is the digram but without it how we now about the error
Answer:
an individual having two different alleles for a specific trait.
Explanation:
