Differences between DNA and RNA

 Differences between DNA and RNA

Download Pdf 

S.N.	Character	DNA	RNA
1.	Full form	Deoxyribonucleic Acid	Ribonucleic Acid
2.	Location	DNA is found in the nucleus, with a small amount of DNA also present in mitochondria.	RNA forms in the nucleolus, and then moves to specialized regions of the cytoplasm depending on the type of RNA formed.
3.	Structure	Long, ladder-like macromolecule that twists to form a double helix.	In contrast to the double helix structure of DNA, RNA is generally single stranded.
4.	Helix Geometry	The helix geometry of DNA is of β-form.	The helix geometry of RNA is of α-form.
5.	Nucleotides	Each DNA nucleotide contains one of four nitrogenous bases, abbreviated A (adenine), G (guanine), T (thymine), or C (cytosine).	Contains the nitrogenous base uracil in place of thymine.
6.	Chain of Nucleotides	Long chain of nucleotides	Relatively short chains
7.	Sugar	DNA contains deoxyribose sugar.	Contains a different sugar (ribose rather than deoxyribose) in its nucleotides.
8.	Base Pairs	Adenine and Thymine pair (A-T) Cytosine and Guanine pair (C-G)	Adenine and Uracil pair (A-U) Cytosine and Guanine pair (C-G)
9.	Ratio of Bases	In case of DNA:  • Adenine = Thymine  • Guanine = Cytosine	In case of RNA:  • Adenine ≠ Thymine  • Guanine ≠ Cytosine
10.	Molecular Weight	2 to 6 million	25,000 to 2 million
11.	Number	For a particular species, the DNA number remains constant for every cell.	The number of RNA may differ from cell to cell.
12.	Molecule	DNA does not usually exist as a single molecule, but instead as a tightly-associated pair of molecules.	RNA may exist as a single molecule.
13.	Propagation	DNA is self-replicating.	RNA is synthesized from DNA on an as-needed basis.
14.	Major enzyme involved in propagation	DNA polymerase	RNA polymerase
15.	Need of Primer	Primer necessary to initiate replication.	No primer is needed for RNA.
16.	Proof-reading activity	Present.	Absent since RNA polymerase lacks the ability to detect errors of base pairing.
17.	Polymer length	DNA is a much longer polymer than RNA. A chromosome, for example, is a single, long DNA molecule, which would be several centimetres in length when unravelled.	RNA molecules are variable in length, but much shorter than long DNA polymers. A large RNA molecule might only be a few thousand base pairs long.
18.	Leaving Nucleus	DNA can’t leave the nucleus.	RNA leaves the nucleus (mRNA).
19.	Complementary forms	Complementary forms are mostly between two DNA strands.	RNA strand can form complementary structures with strands of either DNA or RNA.
20.	Destruction  and re-use	DNA is completely protected by the body i.e. the body destroys enzymes that cleave DNA.	RNA strands are continually made, broken down and reused.
21.	Hydrolyzing enzyme	DNase	RNase
22.	Function	• Storing genetic information • Directs protein synthesis • Determines genetic coding • Directly responsible for metabolic activities, evolution, heredity, and differentiation.	• Transferring genetic information from the DNA to proteins • Carrying it outside the nucleus • Translating it to proteins
23.	Role as Genetic Material	In all organisms other than certain viruses	Very rarely (in some viruses)
24.	Versatility and Usefulness	More stable and holds more complex information for longer periods of time.	RNA is more versatile than DNA, capable of performing numerous, diverse tasks in an organism.
25.	Stability	Due to its deoxyribose sugar, which contains one less oxygen-containing hydroxyl group, DNA is a more stable molecule than RNA. DNA is stable under alkaline conditions.	RNA, containing a ribose sugar, is more reactive than DNA and is not stable in alkaline conditions. RNA’s larger helical grooves mean it is more easily subject to attack by enzymes.
26.	Ultraviolet (UV) Sensitivity	DNA is vulnerable to damage by ultraviolet light.	RNA is more resistant to damage from UV light than DNA.
27.	Mutation Rate	DNA’s mutation rate is relatively lower.	RNA’s mutation rate is relatively higher.
28.	Unusual Bases	Never	May be present rarely
29.	Rate of Renaturation After Melting	Relatively slower	Quick
30.	Types	Chromosomal DNA (nuclear DNA) and Extra-chromosomal (plasmid DNA, mt- DNA, chl- DNA etc.)	Messenger RNA (mRNA) Transfer RNA (tRNA) Ribosomal RNA (rRNA) hnRNA • snRNA • snoRNA • miRNA • siRNA