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>Democracy is when the people of a country are the ones that make decisions about who will govern them by voting (the will of the people). In the United States the people vote for local initiatives, their local representatives, their congressmen, and the president. The local A direct democracy is when the people do not vote for representatives to make the decisions but they vote directly for initiatives, etc whether local or federal. The part of democracy that would be well served in a direct democracy is the local voting because it is direct.</span>
The correct answer to this open question is the following.
Although there are no options attached we can answer the following.
The major U.S. War that helped change the laws that stated that enslaved Africans were not U.S. Citizens was the American Civil War (1861-1865).
Before the Civil War, slavery was the normal thing in the large plantations of the southern states. Indeed, the economy of the South totally depended on slaves to produce the kinds of crops that had to be exported to Europe.
During the war, U.S. War, US President Abraham Lincoln issued the Emancipation Proclamation in January 1863, stating that al slaves in the south had to be free.
After the war, and during the Reconstruction period, white people established a series of laws called the Jim Crow laws that limited black people's rights.
It was the 14th Amendment to the United States Constitution granted citizenship to all the people born in the US or that were naturalized in the US, as was teh as of most black people.
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The largest manufacturing industries in the United States by revenue include petroleum, steel, automobiles, aerospace, telecommunications, chemicals, electronics, food processing, consumer goods, lumber, and mining. A large portion of U.S. industrial output, the United States leads the world in airplane manufacturing.
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The third line returns to the image of silence in the first line. But the silence is slightly different. In the first line, Basho describes a silent pond. In the third line, he writes, simply, “silence.” Because the pond has now returned to silence after the frog splash, this silence seems more significant than the first.
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