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Costa Rica: Animal Rescue
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How old is Nena the Howler monkey?
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Hi, I’m Jim Shields from ABOUT.COM. Today I’m going to teach you about DNA. When you consist in your mother’s womb, started as the union of male sperm cell and female egg cell, fertilized and began into feed us which in turn was born as you. Just began to grow. These initial two cells, sperm and the egg, continued to replicate which we called growth. But how does each cell know what to become? What some cells know become eye cells, others ear cells, still others hair cells? Here’s the DNA. DNA, which short for deoxyribonucleic acid, is like an instruction manual contains in every cell in your body. Each cell has instructions from every cells. DNA practical is forming strands made up of 4 different molecules. Each strand has twin and pairs. Here called double helix which looks like kind of long stair case and has unique ranges of these four molecules, guanine, adenine, thymine and cytosine. These unique range of the four molecules determines what instructions the DNA would give the cell about what kind of cell it become and what kinds of protein it produce to help with other cells. DNA is present in the cells in every life form, whether is bacterium, plant or mammal. And might surprise you to know, if you remove a curled strand of DNA from one of your cells, and stretch to its full length, it will be over 6 feet long. But when it’s curled within cell, it’s less than 10 nanometer. Thanks for watching, to learn more about biology, visit the sound web at about.com.
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