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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It made the government better and more professional and also gave them more training
Answer:Adams cautioned against those who “think it as easy for a nation to change its government, as for a man to change his coat.”[9] Just as he did not think Europe's institutions could be imposed on America, Adams also believed that America's political beliefs could not be imposed on other nations
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The statement recognizes that fiscal policy is not enough to keep an economy at full employment and with low inflation levels for a long period of type.
Explanation:
First of all, it is widely accepted by economists that society faces a short-term trade-off between inflation and employment. The reason for this is that controlling inflation in the short-term requires limiting the amount of money circulating in an economy, and less money means less saving, less investment, and thus, less employment. Hence, we can conclude that balance full employment with low inflation is extremely hard.
Secondly, fiscal policy by itself is not effective in controlling inflation. Inflation is the main goal of monteray policy, which is set by the central bank (in the United States, the Federal Reserve system), and uses a set of tools to achieve the aim of low inflation.
Answer:
Protista and fungi are lower level organisms, which are classified into the kingdom Protista and Fungi, respectively. Protists are mostly unicellular organisms, whereas the fungi are mostly multicellular organisms. ... Protists can be either heterotrophs or autotrophs. Fungi contain a cell wall, which is made up of chitin.
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<u><em>Source is from my own knowledge</em></u>
