Ncert Exercises & Solutions

14.24: Write the important structural and functional differences between DNA and RNA.

The structural differences between DNA and RNA are as follows:

	DNA		RNA
1	The sugar moiety in DNA molecules is β-D-2 deoxyribose.	1	The sugar moiety in RNA molecules is β-D-ribose.
2	DNA contains uracil (U). It does not contain thymine (T)	2	RNA contains thymine (T). It does not contain uracil (U).
3	The helical structure of DNA is double-stranded	3	The helical structure of RNA is single-stranded.

The functional differences between DNA and RNA are as follows:

	DNA		RNA
1	DNA is the chemical basis of heredity.	1	RNA is not responsible for heredity.
2	Proteins are synthesised by RNA molecules in the cells.	2	DNA molecules do not synthesise proteins, but transfer coded message for the synthesis of proteins in the cells.