How are the structures of purines and pyrimidines different?

Answer 1

The main chemical structure difference in purines and pyrimidines is purines have a 5 sided C and N based ring as well as a 6 sided C and N based ring structure. Pyrimidines only have the 6 sided C and N based ring structure, also uracil(unmethylated) replaces thymine(methylated) as a pyrimidine in RNA.

Answer 2

Purines are the basic building blocks of DNA and RNA and are the bases of adenine and guanine: two of the 4 nucleotide bases in DNA. In easiest terms to describe the purine without using a drawing program is draw a benzene ring (6 member ring of carbons with double bonds every other bond). Then number the carbons 1-6. Replace carbon 1 and 3 with a carbon and attach a nitrogen bond to the 4 and 5 carbon. Off one of those nitrogen bonds add a double bond to a carbon. Then connect that C to the nitrogen bond you added off #4 carbon. This will be a 6 member ring with a 5 member ring attached.

Pyrimidines are just the 6 member ring you made in the purine. It is called a 1 3 diazine ring. Pyrimidines are the basis of the other nucleic bases in DNA and RNA called cytosine, uracil, and thymine. Pyrimidines have much lower boiling points and molecular masses than purines.

Answer 3

A purine is a nitrogenous base which has two carbon-nitrogen rings (Adenine and guanine) whilst pyramidine only has one carbon-nitrogen ring (Thymine and cytosine). ----

Answer 4

Purines have a double ring and pyrimidines have a single ring.

Answer 5

Purines are the larger nitrogen base, consisting of a five ring bonded to a six ring. Pyrimidines are the smaller nitrogen base, consisting of a six ring.

Answer 6

A pyrimidine joined with an imadazole ring forms a purine.