DNA vs RNA

The main difference between DNA and RNA is the sugar present in the molecules. While the sugar present in an RNA molecule is ribose, the sugar present in a molecule of DNA is deoxyribose. Deoxyribose is the same as ribose, except that the former has one more OH.

DNA does not usually exist as a single molecule, but instead as a tightly-associated pair of molecules. These two long strands entwine like vines, in the shape of a double helix. This arrangement of DNA strands is called antiparallel. The asymmetric ends of DNA strands are referred to as the 5′ (five prime) and 3′ (three prime) ends. One of the major differences between DNA and RNA is the sugar, with 2-deoxyribose being replaced by the alternative pentose sugar ribose in RNA. The four bases found in DNA are adenine (abbreviated A), cytosine (C), guanine (G) and thymine (T). A fifth pyrimidine base, called uracil (U), usually takes the place of thymine in RNA and differs from thymine by lacking a methyl group on its ring.

Comparison chart

DNA RNA
Stands for: DeoxyriboNucleicAcid RiboNucleicAcid
Definition: A nucleic acid that contains the genetic instructions used in the development and functioning of all modern living organisms(scientists believe that RNA may have been the main genetic material in primitive life forms). A single-stranded chain of alternating phosphate and ribose units with the bases Adenine, Guanine, Cytosine, and Uracil bonded to the ribose. RNA molecules are involved in protein synthesis and sometimes in the transmission of genetic information.
Job/Role: Medium of long-term storage and transmission of genetic information Transfer the genetic code needed for the creation of proteins from the nucleus to the ribosome.
Unique Features: The helix geometry of DNA is of B-Form. DNA is completely protected by the body, i.e., the body destroys enzymes that cleave DNA. DNA can be damaged by exposure to Ultra-violet rays The helix geometry of RNA is of A-Form. RNA strands are continually made, broken down and reused. RNA is more resistant to damage by Ultra-violet rays.
Predominant Structure: Double- stranded molecule with a long chain of nucleotides A single-stranded molecule in most of its biological roles and has a shorter chain of nucleotides
Bases & Sugars: Deoxyribose sugar; phosphate backbone; Four bases: adenine, guanine, cytosine and thymine Ribose sugar; phosphate backbone. Four bases: adenine, guanine, cytosine, and uracil
Pairing of Bases: A-T(Adenine-Thymine), G-C(Guanine-Cytosine) A-U(Adenine-Uracil), G-C(Guanine-Cytosine)
Stability: Deoxyribose sugar in DNA is less reactive because of C-H bonds. Stable in alkaline conditions. DNA has smaller grooves, which makes it harder for enzymes to "attack" DNA. Ribose sugar is more reactive because of C-OH (hydroxyl) bonds. Not stable in alkaline conditions. RNA has larger grooves, which makes it easier to be attacked by enzymes.
Propagation: DNA is self-replicating. RNA is synthesized from DNA when needed.
DNA helix structure
DNA helix structure
Structure of RNA (hairpin loop from pre-mRNA)
Structure of RNA (hairpin loop from pre-mRNA)

Contents

Videos explaining the differences

Further Reading

Some good books on DNA and RNA are available on Amazon.com:

Related Articles

References

Comments: DNA vs RNA

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Anonymous comments

The chart language "A single-stranded chain of alternating phosphate and ribose units with the bases Adenine, Guanine, Cytosine, and Thymine bonded to the ribose. RNA molecules are involved in protein synthesis and sometimes in the transmission of genetic information." is wrong! It should have Uracil replacing the Thymine as the base bonding with adenine in RNA. You had it right in the language at the start of the article.

50.✗.✗.117 on 2013-02-19 02:42:54

Why does the change of sugar in the base ribose for RNA and deoxyribose for DNA cause the observed structural differences: RNA mainly single stranded (but can be double stranded), DNA mainly double stranded. Does the ribose destabilize double RNA stands? Or is it due to the uracil base?

87.✗.✗.86 on 2012-11-04 15:59:03

This 16 minute video completely made my 6 hour lecture come together! Now I TOTALLY GET IT!! Lightbulb! Thank you!

69.✗.✗.231 on 2012-09-12 01:16:24

The video is very helpful. Thank you!

99.✗.✗.33 on 2012-08-04 03:04:44

We have two test tubes(not labelled) where if one has RNA, then the other contains DNA. So,what will be the test to distinguish between these two?

117.✗.✗.67 on 2012-02-01 15:08:49

rna is a base for formation of dna so its a nice diffrent

106.✗.✗.212 on 2012-01-10 09:38:00

RNA is different from DNA in such a way that RNA is found throught the cell while,DNA is found in nucleus only.........

182.✗.✗.74 on 2011-01-23 08:23:03

Another difference is that RNA molecules can have a much greater variety of nucleic acid bases. DNA has mostly just 4 different bases with a few extra occasionally. http://www.justcancer.org

113.✗.✗.93 on 2010-06-04 10:28:35

No, DNA is DEOXYRIBOnucleic acid so it is deoxyribose

163.✗.✗.10 on 2010-02-09 18:14:23

"While the sugar present in a DNA molecule is ribose, the sugar present in a molecule of RNA is deoxyribose". this should be swapped

68.✗.✗.190 on 2008-05-13 19:22:44

Recent studies from NASA have revealed that the structural backbone of DNA (originally thought to be made of phosphate) can also be made of arsenic, in which broadens the spectrum of life, making it just that much more possible for extraterrestrial life to exist. http://www.youtube.com/watch?v=W_Nz_6Pbydo

99.✗.✗.171 on 2010-12-16 19:25:13

For Convenience sake, you might remember the list of the hetrocyclic amine in DNA by these word: The Amazing Gene Code (T.A.G.C.) for Thymine, Adenine, Guanine, Cytosine....respectively...... Mgbeahuru Chidi Christian, Dept. of Biochemistry, Faculty of Biological Science, UNN, Nigeria. +(234)8068101366

212.✗.✗.200 on 2010-06-17 15:10:41

self replication of DNA occurs in 03 stages. 01.Unwinding 02.Complementary bases of free neucleotides are attached by base pairings. 03.Linkage

112.✗.✗.246 on 2010-05-29 06:13:35

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