1. Three compounds are needed to make a nucleotide OH O OH OH deoxyribose P O OH OH OH and phosphoric acid N N NH N NH 2 a base (this one is adenine) They combine through two condensation reactions (condensation means ‘splitting out’ water, H 2 O) Click to follow the formation of the nucleotide from these three compounds Formation of a nucleotide

2. OH O OH OH deoxyribose N N NH N NH 2 a base a condensation reaction N O OH OH N N N NH 2 OH 2 And now a phosphate group is added by reaction with phosphoric acid – click to see the reaction

3. P O OH OH OH N O OH OH N N N NH 2 OH 2 a condensation reaction Click for a larger diagram of the nucleotide

4. The nucleotide formed from: deoxyribose, adeninine and phosphoric acid is N O O OH N N N NH 2 P O OH OH This is called AMP ReplayReplay Close windowClose window