1 Set of hunches. 2  If a theory is a set of hunches, it means we arenât yet sure we have the answer. 3  Theories always involve an element of speculation or conjecture. 4  A theory is not just one inspired thought or an isolated idea.  A theory offers some sort of explanation.
Uracil is paired with thymine in RNA and it is paired with Adenine in DNA. In DNA transcription (from DNA to RNA), uracil pairs with adenine. in regular DNA replication adenine pairs with thymine.
Bases are classified into two types: the purines, A and G, and the pyrimidines, the six-membered rings C, T and U. Uracil (U), takes the place of thymine in RNA and differs from thymine by lacking a methyl group on its ring. Uracil is not usually found in DNA, occurring only as a breakdown product of cytosine.