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What is DNA made of?
Answer 1:

DNA is a pretty simple molecule when you consider its awesome role in life. DNA (deoxyribonucleic acid) gets its name from its parts.

The center of every DNA molecule is a sugar called Deoxyribose. Like other single-unit sugars, it has 6 carbon atoms. Like all sugars I can think of, its name ends in "ose." This sugar ring is attached to other sugar rings by phosphate groups to make long chains.

The reason that DNA can carry information is because the other thing attached to the sugar is one of 4 bases: adenine (A), thymine (T), guanine (G), and cytosine (C). Each base is made of different atoms, so they interact with each other in specific ways. G and C bond with each other and A and T bond with each other. This makes the two chains into one double chain that's like a ladder with the bases as the rungs. This seems like a simple thing, but it allows DNA to make copies of itself. That's why DNA can be passed from one generation of cells to the next.

Here's how it works. Suppose you wrote "secret code" on a piece of paper, then wrote a mirror image of each letter on another piece of paper. If you gave the backwards copy to a friend, he or she could make a mirror image of each letter and be back to the original message. If I have a string that says AATCGC, the only bases that will line up with it will be TTAGCG. Then when this second string is copied, it will give me AATCGC.

Here's a good picture: DNA

If one A lined up with a C by accident (a "mutation"), what would happen to all future copies of this strand of DNA?



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