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:
A
Explanation:
When petroleum products such as gasoline are burned for energy, they release toxic gases and high amounts of carbon dioxide, a greenhouse gas. Carbon helps regulate the Earth's atmospheric temperature, and adding to the natural balance by burning fossil fuels adversely affects our
Answer:
Meristematic tissue
Explanation:
Meristematic tissue contains actively dividing cells that result in formation of other tissue types (e.g. vascular, dermal or ground tissue). Apical meristematic tissue is found in buds and growing tips of plants.
Answer:
What I expect would happen: First, there would be no clouds. Lack of clouds would mean there would be no rain and the average temperature of the Earth would increase, resulting in large areas of land becoming desert.
Explanation:
The water cycle is the process where water falls as rain, is transported via rivers and streams to lakes and oceans, evaporates into the sky, condenses into clouds, and falls as rain again. Here's a diagram:
water.usgs.gov
water.usgs.gov
So what would happen if there were no condensation stage?
The condensation stage is the one where water vapour gathers together into clouds (and when the clouds become heavy enough with vapour, release water as rain). So the first answer is that there would be no clouds.
Without clouds, I foresee a few things happening:
From clouds come rain. With no clouds, there would be no rain.
Clouds move moisture from lakes and oceans (where it evaporates up) to mountains and other places inland that spark rainfall. And so vast stretches of land would become desert.
Clouds reflect sunlight and help cool the Earth. With no clouds, the average temperature of the Earth would increase significantly.
And so to summarize what I expect would happen. First, there would be no clouds. Lack of clouds would mean there would be no rain and the average temperature of the Earth would increase, resulting in large areas of land becoming desert.
Explanation:
