and why does cytosine bond with guanine?
2006-08-27 10:33:50 · 4 answers · asked by hiya 1 in Science & Mathematics ➔ Biology
Those are the base pairs that make up the structure of DNA. The reason the pairing is so specific is because of their chemical structure. A and T easily form 2 hydrogen bonds with each other and C and G easily form 3 hydrogen bonds between each other. It is called complementary pairing. Adenine and guanine are called purines and thymine and cytosine are pyrimidines and purines are only compatible with pyrimidines. These bonds are formed because they are the most energetically favorable and stable based on the structure of these chemicals. I would recommend looking up things like this on Wikipedia because it is great for answers on everything.
2006-08-27 10:52:13 · answer #1 · answered by Anonymous · 3⤊ 1⤋
I believe it's because adenine and thymine have two bonds between each other while cytosine and guanine have three. Also, pyramidines always bond with purines.
2006-08-27 17:52:29 · answer #2 · answered by Jazzie 2 · 0⤊ 1⤋
I don't know. I guess that's just what they do. I didn't pay too much attention in high school biology. And it was 5 years ago.
2006-08-27 17:40:01 · answer #3 · answered by *AstrosChick* 5 · 0⤊ 2⤋
as far as i know its due to protiens that are on the one half of the base pair .
2006-08-27 17:46:03 · answer #4 · answered by dooralarm 2 · 0⤊ 3⤋