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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<span>The biggest problem is that </span>the type of the autoshaped reaction fluctuates with the sort of reinforcer that is utilized.Autoshaping some of the time called "sign tracking" is any of an assortment of exploratory methodology used to traditional conditioning. In the methodology a reinforcer is matched with a stimulus that is independent of the subjects conduct until the subject makes a reaction to the stimulus.
On news sites like the new york times or the wall street journal the domain end with .com
The purpose of the domain name : it serves to identify internet resources such as computers networks and services with a text-based label that is easier to memorize than the numerical addresses used in internet protocols.
For humans, it's much easier to remember the address of a Web site using a name rather than an IP address. IPV4 addresses were complicated but nothing compared to IPv6 addresses . So, we came with the idea of using this central database that keeps the relationships between domain names and IP addresses. Also, if the Web site changes address (or host), that is completely transparent to the user because he doesn't know (nor care!) what's the site's address.
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The answer is Green Revolution
I hope that helped
Answer:
The railway allowed people to flock to cities and allowed people to travel newer places as well. Business boomed due to the railway with the mass increase of people and goods. All in all, the railway was a major success in all aspects of the Industrial Revolution especially in time and distance.
Explanation:
The technological advances and religious and social movements of the Antebellum Period had a profound effect on the course of American history, including westward expansion to the Pacific, a population shift from farms to industrial centers, sectional divisions that ended in civil war, the abolition of slavery
