Monomers are single-unit molecules that bind to each other to form long chains or polymers. The monomers of DNA and RNA are
Both DNA and RNA are nucleic acids in all most all the cells.
Both molecules are large strands of nucleic acids and are made of nuclear bases and carbohydrate monomers.
As the name indicates, DNA (deoxyribonucleic acids, RNA (ribonucleic acids) have a similar structure and are made of similar monomers.
These two nucleic acids, DNA and RNA, are found in all the living cells, virus capsid, and even in space. Further, they can be made in the laboratory.
Monomers of nucleic acid DNA and RNA
Monomers of DNA
DNA is present as a double-stranded structure with two strands aligned in a helix.
DNA has five monomers, of which one is a carbohydrate monomer while the remaining four are nuclear bases.
The carbohydrate monomer is a five-carbon sugar, namely deoxyribose.
The four nuclear bases include two purine bases, namely
and two pyrimidine bases, namely
Monomers of RNA
Like DNA, RNA also has a single carbohydrate monomer, namely the ribose sugar, a five-carbon sugar.
Then there are four nuclear bases, of which two are purine bases like
and two pyrimidine bases as
So the purine bases are the same monomers in both the DNA and RNA but the pyrimidine bases are different between these two nucleic acids. There is uracil instead of thymine in the RNA strand.
In both these molecules, the sugar monomers are held together to form a long strand by a phosphodiester bond. At the same time, the nuclear bases are bound to the carbohydrate monomer.
The DNA molecule is a double-strand structure, while the RNA is a single strand structure.
The double-strand structure of DNA is possible due to the hydrogen bonds between the nuclear bases of both chains.
DNA is the genetic material and is more stable than RNA. DNA resides in the nucleus as a double-strand structure and a single-strand structure in mitochondria. RNA is a less durable genetic material and is present mostly in the cytoplasm of the cell.