Directionality

An RNA molecule is a chain of nucleotides with two distinct ends, called 5' ("five-prime") and 3' ("three-prime"). By convention, an RNA sequence is written and numbered in the 5' to 3' direction.

 

==Introduction==

Nucleotides joined by bonds between sugar and phosphate groups. Two distinct positions on the sugar ring are bound to phophate - the 5' and 3' positions. RNA is customarily numbered and written in the same direction as it is synthesized by all life forms.