Logged out
Access All our Essays in an Instant
Swap your work for FREE access, or pay £4.99 for instant access
They contains the instructions that make every single living organism on the planet. DNA stands for deoxyribonucleic acid and RNA for ribonucleic acid. They are polymers (long chain molecules) made from nucleotides.
Member rating: No Rating | Words: | Submitted: Mon Dec 19 2005
Page Preview
On the left is an image preview of every page of this document, and below are the first 150 words with formatting removed:
DNA DNA and its close relative RNA are perhaps the most important molecules in biology. They contains the instructions that make every single living organism on the planet. DNA stands for deoxyribonucleic acid and RNA for ribonucleic acid. They are polymers (long chain molecules) made from nucleotides. Nucleotides have three parts to them: * a phosphate group, which is negatively charged. * a pentose sugar, which has 5 carbon atoms in it. In RNA the sugar is ribose. In DNA the sugar is deoxyribose. Nucleotides * a nitrogenous base. There are five different bases. The bases are usually known by there first letters only. The base thymine is found in DNA only and the base uracil is found in RNA only. Nucleotide Polymerisation Nucleotides polymerise by forming bonds between the carbon of the sugar and an oxygen atom of the phosphate. The bases do not take part in the polymerisation, so the chain is held...
To see the full version of this document, and 145,348 others
