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The complete history of the Universe -- from the Big Bang to 200 my into the future


History of the Universe eBook. 398 pages, 300 illustrations only £5.99

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Base Pairing

The bases were able to stick together edge to edge because of hydrogen bonds. In order to make a regular pattern which will allow the pairs of bases to stack on top of each other, a large base has to stick to a small one.

Cytosine and guanine stick together with three hydrogen bonds.

Cytosine (left) sticks to guanine (right) with three hydrogen bonds

In the diagram you can see where the molecules touch.

Thymine and adenine stick together with two hydrogen bonds.

Thymine (left) can stick to adenine (right) with two hydrogen bonds

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History of the Universe eBook. 398 pages, 300 illustrations only £5.99

eBook only £5.99
398 pages, 300 images

"I find the science fabulous...an extremely useful teaching tool."
Professor David Christian.