What's the Deal with DNA?

DEOXYRIBONUCLEIC ACID!

That's what DNA stands for. It's a super important molecule inside the nucleus of every single cell in your body. It...

• Controls all the activities of the cell



• Contains the information to make new cells



• Provides instructions for making proteins

In other words, it is nothing less than the Blueprints for Life! Ever wondered why your eyes, hair, and skin are the color they are and not something else? Or why some people have dimples, are double-jointed, can roll their tongue into funny shapes, and other can't? It's all because of DNA.

DNA is a long string of molecules bonded together. The first scientists to discover the odd shape of DNA were James Watson and Francis Crick, with the help of x-ray photographs taken by Rosalind Franklin (nice last name, huh?). Together they determined that DNA is shaped like a twisted ladder called a double helix.

The sides of the double helix are made of sugar and phosphate molecules. The center rungs that stretch in between are called nucleotides, and there are 4 types.

Adenine (A) Thymine (T)
Cytosine (C) Guanine (G)

In the 1950's, a scientist named Erwin Chargaff discovered that the amount of Adenine (A) in DNA always equaled the amount of Thymine (T), and the amount of Cytosine (C) always equaled the amount of Guanine (G). That's because Adenine (A) always pairs with Thymine (T), and Cytosine (C) always pairs with Guanine (G). This is known as Chagraff's Rule.

Chagraff's Rule:

A -- T C
-- G
T -- A G --
C

Because A and T always go together and C and G always go together, if you're missing one half of the DNA it can easily be rebuilt by checking out the other half. In fact, this is how DNA reproduces.