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:
Under the Truth in Lending Act a consumer obtains a loan that is secured by a principal residence the has the right to rescind in three business days with the exception of a purchase and construction of a principle residence. This statement is TRUE.
Explanation:
The 'Truth in Lending Act' ( TILA) ensures that there is a specific way informed to use credit cards. It promotes the exposure of its terms and costs so that there is a standard way of calculating the cost of loan borrowing. This is a federal law in which lenders are required to provide clients with all the information of loan cost so that they can compare various loans that are given.
Under this act, debtors can cancel certain transactions for a period of three days from the date of transaction or the date from which notice has been given of their right to withdraw, whichever is later. Thus, the statement is TRUE.
Answer:
they believe online interaction can enhance face-to-face interaction especially if one is looking up information relevant to the conversation
Explanation:
In face to face communication there is both verbal and non verbal communication where is bodily and facial gestures depics degree of involvement while in online communication there is only written communication hence here information exchange is of prime importance hence in online information if degree of information exchange is high then what other person is doing is of least concern.
