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HOW TO EXTRACT YOUR OWN DNA Collect a sample of DNA from your cheek cells with this great home experiment. Apparatus required : -- concentrated alcohol (isopropyl alcohol), colored sports drink, paper cup, jar or a test tube, dish soap, pineapple juice, wooden skewer, microscope. There are five steps to extract DNA given below. STEP ONE : - Prepare your alcohol For this experiment to work you need to get some highly concentrated alcohol. This can be easily obtained from your local pharmacy in the form of isopropyl alcohol . The closer you get to 100 per cent alcohol, the better success you will have. Around 24 hours before you start, place your alcohol in the freezer. It won’t solidify due its very low freezing point, but needs to be ice cold for the experiment to work. STEP TWO : - Produce your cheek-cell mixture Take a generous mouthful of a lightly colored sports drink and swirl it around your mouth. Aim to keep this going for a minimum of two minutes...

Why does popcorn pop? Popcorn kernels contain starch and a small amount of water. When cooked, the water inside expands as it evaporates into steam, and turns the starch into a gooey paste. The hard shell manages to contain it until the pressure gets too high and it ruptures with a pop, which is typically at a temperature of 180 degrees Celsius (356 degrees Fahrenheit). The drop in pressure and escaping steam causes the starch to expand and solidify as it cools, forming puffy white flakes.     Why do avocados go brown quickly? When an avocado is cut open and its flesh is exposed to oxygen, the enzyme polyphenol oxidase converts chemical compounds called phenols into quinones. These quinones produce polymers called polyphenols, which turn the flesh a brown color. Of course, most fruits turn brown eventually, but the process occurs more quickly in avocados because they contain more polyphenol oxidase. To slow this down, wrap i...

WHAT IS SALIVA? Humans can produce an incredible two liters (half a gallon) of saliva each day. It is made up of 99.5 per cent water, so how is it able to perform so many important functions in our mouths? The answer lies in the remaining 0.5per cent, which contains a host of enzymes, proteins, minerals and bacterial compounds. These ingredients help to digest food and maintain oral hygiene. As soon as food enters the mouth, saliva’s enzymes start to break it down into its simpler components, while also providing lubrication to enable even the driest snack to slide easily down the throat. Saliva is also important in oral health, as it helps to protect teeth from decay and also controls bacterial levels in the mouth to reduce the risk of infection. Without sufficient saliva, tongue and lip movements are not as smooth, which, in extreme cases, can make it very difficult to speak. With advanced scientific techniques and research, an individual’s saliva can reveal a great deal of...

WHAT WOULD THE WORLD BE LIKE WITHOUT MAGNETS? No navigation : - In uncharted landscapes, explorers rely on compasses to find their way, using a floating magnetic needle to point to Earth’s magnetic north pole. It is thought that the first practical compass was made in 1274, providing an invaluable tool for navigating the seas and oceans, and eventually leading European explorers to the Americas.   No data storage :- From cassette and video tapes, to floppy disks and hard disks, many of our early methods of digital data storage relied on magnetic tape. To store the information, a current is passed through a coil of wire, creating a magnetic field that changes the direction of the magnetic domains of tiny metal particles embedded in the tape.   No radar (or microwaves) :- The radio waves used in radar, and the microwaves used to cook your dinner, are produced by a p...