Nucleic Acids We will consider briefly the organization of nucleic acids now, only to show parallels with the other polymers. We will cover them properly later. Here the monomers are nucleotides . These are fairly complex molecules, but there are only a few kinds. This ring is the new component, and there are two kinds, single ring pyrimidines and double ring purines .
Nucleotides are combined phosphate, sugar, and base.
In organisms nucleotides do several things. The first is as a simple monomer nucleotide with three phosphates attached in a row. This is usually adenosine triphosphate or ATP , which is involved in energy storage and transmission, as we will see later. Single nucleotides are also involved as messengers of various signals in the body, the major one being cyclic AMP , where the single phosphate bonds around to the base forming a second ring. This is an internal messenger in many hormone signalling systems we will consider later.