What is a nucleotide?
A nucleotide is the basic unit that makes up DNA. A singular nucleotide is made up of x3 components:
- A base (A, T, C or G)
- 5 Carbon sugar (deoxyribose = DNA or ribose = RNA)
- Phosphate group (forms a bond between the sugar molecules in a DNA chain = phosphodiester bond) Bases There are x4 different nitrogenous bases that comprise DNA.
- Adenosine
- Cytosine
- Thymine
- Guanine
There are two groups of nucleotides pyrimidines and purines
Pyrimidines Thymine and Cytosine are the smallest of the 4 bases. With only 1 ring in their structure. In RNA, Thymine is replaced by Uracil all other bases are the same
Purines Adenosine and Guanine are purines. Their structure contains a pyrimidine ring + a smaller 5 sided ring. Therefore making a 2 ringed structure.
HA
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