1. Samples of a microbial colony obtained from the natural environment are not pure culture. They are mixed cultures because the environment consists of an array of microorganisms and not one specific organism. A sample obtained from the natural environment such as water or soil may contain several species of microbes that need to be further isolated to obtain a pure culture.
2. Isolation streak plate technique involves the dilution of the sample several folds and then streaking a small amount using a sterile inoculation loop on an agar plate in a zig-zag manner. This is done to obtain a pure culture of bacteria from a mixed population by separating the microprocessor. When the sample is diluted into a small concentration and is streaked onto agar placed, widely spaced, discrete colonies of bacteria can be observed. These isolated colonies can be further cultured to obtain pure cultures by picking and re-streaking them on fresh agar plates.
3. A microbial colony is considered a pure culture because it consists of single species. A single species of bacteria cluster and form an isolated colony on an agar plate which can be further plated on fresh medium.
3-1 - If your agar plate shows discrete uncluttered colonies then you have obtained an isolated colony. The following picture might help you to understand.
3-2. If you subculture isolated microbes into a sterile nutrient broth without any contamination, it will still be considered pure culture because it is single isolated species in a sterile aseptic environment of the nutrient broth.
3.3. A pure culture can become a mixed culture due to contamination. This could be caused by airborne bacteria if your conditions are not aseptic. Contamination is possible if the work area is not clean and sterile or if the glassware is not sterile. The contamination can transform your pure culture into a mixed culture and is hence problematic. So, it is very important to maintain a sterile and aseptic environment, glassware, and instruments.
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Answer:
The constitution
Explanation:
Constitution is commonly known as the ultimate or supreme law of used in governing a particular land (Country).
The constitution ensure that there is Separation of Powers between the different branches of government to make sure that non enroach on the power of the other and importantly that no one person, branch or group becomes too powerful. It also has the Checks and Balances as it is the principle that state that the three branches of government which are legislative, Executive, and Judicial arms or branch of government should have some power each other that is the ability to check or limit the power of the other branches of government.
The correct answer is letter B
Consumer surplus is therefore a measure of economic well-being, and the higher its value, the greater the benefit to consumers in that market. We will thus have that the producer surplus is equivalent to the area of the polygon determined by the supply curve and a certain marketing price.
Consumer surplus is one component of the economic surplus, a concept that gained popularity with the English economist Alfred Marshall.
Answer:
I guess they would feel better
