Steroids
The chemical messengers in our bodies are known
as
Hormones
which are organic
compounds synthesized in glands and delivered by the bloodstream to certain tissues in
order to stimulate or inhibit a desired process.
Steroids
are a type of hormone which are
usually recognized by their tetracyclic skeleton, consisting of three fused six-membered
and one five-membered ring, as shown in the diagram below. The four rings are
designated A, B, C & D as noted in blue, and the numbers in red represent the carbons.