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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The study found that "<span>The boys who displayed feminine behaviors were much more likely to be homosexual or bisexual by the time they reached their late teens".</span>
Richard Green's Investigation taken after the advancement of
sexual orientation in two gatherings of young men:
1. Group 1 alluded to a mental well-being facility due to
their "feminine" conduct
2. Control group of young men who showed normally manly
conduct in youth
Approx. 75% of the beforehand feminine young men were either
bisexual or gay, just 4% in the control group were like that. This is less
valid for young females.
Answer:
B) wwl, wwll, european union, cold war
Explanation:
Answer:
marginality
Explanation:
Keyshawn's ethnic identity seems to be a marginality. This means that his African American origin seems to put Keyshawn in a position that makes it difficult for him to actualize his dreams. Marginality in this context means the condition or state of an individual being put on the margins of society or being excluded from achieving a goal/being prevented from access to certain aspects of society due to certain reasons such as race and ethnicity.
I believe the answer is: Defeated
The defeated group in hetherington's term refers to the people who are failing in maintaining the marriage commitment with their partner.
The problems that caused the failure mostly come from either emotional issues or personal issues between the couples.
