What is DNA?

DNA carries the genetic information that codes for instructions in our body and other organisms. DNA is deoxyribonucleic acid. It is found in the shape of a double helix. The conclusion that DNA is in the shape of a double helix comes from the scientists Francis Crick and James Watson. They based their work off another scientist called Rosalind Franklin.DNA is made up from a sequence of nucleotides which makes up the backbone. A single nucleotide is made up of a five-carbon sugar, a phosphate group and a nitrogenous base. The five-carbon sugar, pentose sugar called deoxyribose as it does not have an oxygen on one of its carbons (hence the "de"). There are 4 types of bases each singular nucleotide can consist of:Guanine (G) Cytosine (C) Thymine (T) Adenine (A). 2 "chains" form of the nucleotides which make up a sugar phosphate backbone to hold the DNA in a helical shape.

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