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How does cloning work?

Cloning that occurs in nature can work by asexual reproduction, when single-celled organisms produce genetically identical offspring by copying a single cell from themselves. Natural cloning can also work in mammals, when a fertilized egg splits and creates identical twins that carry almost identical DNA.\nArtificial cloning includes gene, reproductive and therapeutic cloning. Gene cloning is done by a different process than reproductive and therapeutic cloning and is done to produce copies of genes for researchers to study. The procedure for gene cloning involves insertion of a gene from one ..

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What do you need plastic recycling codes for?

Each number indicates a different type of plastic, and thus, chemical makeup. Code 1 indicates polyethylene terephthalate and is often found in plastic water bottles. Code 2 is used for high-density polyethylene, the plastic often used in milk and water jugs. Code 3 stands for Polyvinyl Chloride, which is often found in food or detergent containers, mattress covers, bibs, peanut butter jars and certain bottles, as well as cling wrap. Low-density polyethylene, a plastic often found in soft, more flexible bags, such as those found at a grocery store, is labeled with Code 4. Polypropylene, labele..

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What does the stomach do?

The top of the stomach is called the fundus. The central part of the stomach is the cardiac portion, while the lower part is called the pyloric portion. At the end of this portion is the pyloric sphincter, which opens to allow entry into the duodenum, which is the upper part of the small intestine.\nThe stomach is muscular, which allows it to churn food. It secretes mucus to lubricate the food and hydrochloric acid and enzymes to help break it down.

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How is ecological balance maintained?

An example of negative feedback that helps to maintain the balance of nature is found in predator/prey ratios. When the population of prey animals expands, the food available to predators is more abundant. The environment then supports an expansion of the population of predators, who then consume more prey and reduce the population to a sustainable level. This reduction in prey populations then forces a commensurate drop in predator numbers.

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How hot is the center of the earth?

The Earth's inner core is hypothesized to be a solid iron mass despite the high temperature; this is due to extremely high pressure. It is thought that the inner core rotates within the Earth's outer core, which is composed of liquid iron and sulfur. The Earth's outer core is thought to be slightly cooler than the inner core, at a range of 7,280 to 10,340 degrees Fahrenheit.

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What are the main organs of the digestive system?

Human digestion begins in the mouth. As soon as food enters the mouth, enzymes found in the saliva begin to process and break down the food. Next, the food is swallowed and enters the esophagus, which is a muscular tube that contracts to move food into the stomach. Once in the stomach, food is mixed and ground. The stomach also secretes acid and enzymes to break down the food even more. Next, the food enters the small intestine. The pancreas, liver and gallbladder secrete enzymes, acids and bile into the small intestine to help further break down the food. The small intestine is also the place..

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How do I make an ammonium nitrate cold pack?

Ammonium nitrate cold packs are popular for treating sports, camping and schoolyard injuries because they are portable and require no refrigeration. Ammonium nitrate cold packs are available in most stores, but it is possible to make one at home using a few ingredients. Ammonium nitrate is a white, granular substance that is mainly used in fertilizer. It is available as a pure chemical, but is difficult to obtain in large quantities, since it is a semi-controlled substance sometimes used in explosives.\nWhen making a cold pack at home, observe proper safety precautions. Ammonium nitrate is a h..

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What month is August in the calendar year?

August was originally named Sextilis because it was the sixth month of the ancient Roman calendar. When January and February were added to the year in approximately 700 B.C., August became the eighth month. In 8 B.C., it was officially named August in honor of Augustus Caesar.\nIn the modern Western world, August is considered the busiest month for tourism because it falls during most schools' summer breaks. The birthstone for August is the peridot or onyx, and the flower is the poppy or gladiolus.

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What is soil degradation?

Common examples of soil degradation include erosion, loss of organic matter, declining fertility, excessive flooding and the effects of toxic chemicals and pollutants. There have been many links between climate change and the soil conditions of land areas. Because of these links and the risks involved, many governments are creating programs to aid in the restoration and preservation of soil conditions.

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What is the meaning of Zn (CIO3)2?

Zinc chlorate has a solubility in water of 200 grams per 100 milliliters at 20 degrees Celsius. It is classified as a hazardous substance due to its strong oxidizing properties and its propensity to explode when heated or under fire. It is considered a health hazard and causes burns and irritations when in contact with the skin or the eyes. It is also toxic when inhaled or ingested and can cause death.

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