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:
<h3>4. all of the above.</h3>
Explanation:
The concept of utilitarianism simply asserts that actions are determined, whether they are good or bad, by the results it brings. It takes into account only the results of an action. The purpose of this concept is to make a society better by maximizing the amount of good things while reducing the amount of bad things.
Utilitarians rejects moral conducts and systems controlled by a board of higher authority. And does not belief in the orders and rules which are constructed on the lines of customs, traditions, or other supernatural elements.
Here, the reasons to reject utilitarianism includes all the given reasons. Utilitarianism believes that actions done by an individual for his own pleasure is a basic fundamental reasoning. It does not take into account the greater pleasure of the people.
Utilitarianism advocates individual's interest and ignores the interests of other people focusing only on one's egoistic self interest in their quests for the greatest pleasure.
Utilitarians believe that humans are capable of distinguishing good and bad by nature. Therefore, every action done by him/her is for the purposes of achieving the greatest pleasure.
Answer:
jeewanma santusti lina rw dina ka lagi mun safa rw ramro soach bewahar ko aawasekta huna aawasek xa ina vane hamro ramro soach na vae hami ramro garna sakdainam
