Nitrogenous bases are the parts of RNA and DNA that are involved in pairing up (see also base pairs). These include cytosine, guanine, adenine, thymine (DNA) and uracil (RNA).
... 200s 210s 220s 230s - 240s - 250s 260s 270s 280s 290s Years: 237 238 239 240 241 - 242 - 243 244 245 246 247 Events Patriarch Titus[?] succeeds Patriarch Eugenius ...