Redirected from Heterocyclic
That is, unlike the carbon-only ring like in benzene and napthalene, there are other elements in the backbone, such as in pyrimidine and purine.
... no husband present, and 37.6% are non-families. 27.7% of all households are made up of individuals and 14.5% have someone living alone who is 65 years of age or older. ...