Purines and Pyrimidines - Revision history

Nnjm2 at 09:52, 6 December 2017

2017-12-06T09:52:53Z

← Older revision		Revision as of 09:52, 6 December 2017
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two distinct [[~~Nitrogenous_base~~\|nitrogenous]] nucleotide bases which form the five nucleobases present in~~ ~~[[DNA\|DNA]] and [[RNA\|RNA]]<ref name="[1]">Berg JM, Tymoczko JL, Gatto GJ Jr, Stryer L. Biochemistry. W. H. Freeman; 2015.</ref>. Pyrimidine bases are [[~~heterocyclic~~\|heterocyclic]] compounds which consist of a single carbon ring containing two nitrogen atoms, whereas purine bases consist of two carbon rings (a pyrimidine ring fused to an [[Imidazole\|imidazole]] ring) containing a greater number of nitrogen atoms, so their structures provide distinct differences splitting nucleobases into two types. There are two types of Purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three types of Pyrimidines: [[Cytosine\|Cytosine]], [[Thymine\|Thymine]]~~ ~~(which is only used in DNA, as its substituted by Uracil in RNA during [[DNA transcription\|transcription]])~~ ~~and [[Uracil\|Uracil]] (which is only present in types of~~ ~~[[RNA Polymerase II\|RNA]], such as~~ ~~[[MRNA\|mRNA]] and [[TRNA\|tRNA]]~~ ~~substituting Thymine)<ref name="[2]">Alberts B, Johnson A, Lewis J, Morgan D, Raff M, Roberts K, et al. Molecular Biology of the Cell. Garland Publishing; 2014.</ref>.~~ ~~		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two distinct [[Nitrogenous base\|nitrogenous]] nucleotide bases which form the five nucleobases present in [[DNA\|DNA]] and [[RNA\|RNA]]<ref name="[1]">Berg JM, Tymoczko JL, Gatto GJ Jr, Stryer L. Biochemistry. W. H. Freeman; 2015.</ref>. Pyrimidine bases are [[Heterocyclic\|heterocyclic]] compounds which consist of a single carbon ring containing two nitrogen atoms, whereas purine bases consist of two carbon rings (a pyrimidine ring fused to an [[Imidazole\|imidazole]] ring) containing a greater number of nitrogen atoms, so their structures provide distinct differences splitting nucleobases into two types. There are two types of Purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three types of Pyrimidines: [[Cytosine\|Cytosine]], [[Thymine\|Thymine]] (which is only used in DNA, as its substituted by Uracil in RNA during [[DNA transcription\|transcription]]) and [[Uracil\|Uracil]] (which is only present in types of [[RNA Polymerase II\|RNA]], such as [[MRNA\|mRNA]] and [[TRNA\|tRNA]] substituting Thymine)<ref name="[2]">Alberts B, Johnson A, Lewis J, Morgan D, Raff M, Roberts K, et al. Molecular Biology of the Cell. Garland Publishing; 2014.</ref>.

	~~'''~~Base pairing~~'''~~		=== Base pairing ===

	----		Purines always bond with pyrimidines via [[Hydrogen bonds\|hydrogen bonds]] following the [[Chargaff's Rules\|Chargaff rule]] in [[DsDNA\|dsDNA]], more specifically each bond follows [[Watson-Crick base pairing\|Watson-Crick base pairing]] rules<ref name="[3]">Griffiths AJF, Miller JH, Suzuki DT, Lewontin RC, Gelbart WM. Structure of DNA. 2000 [cited 2017 Dec 6]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK21786/</ref>. Therefore adenine specifically bonds to thymine forming two hydrogen bonds, whereas guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. During transcription and [[Translation\|translation]] as thymine is substituted by uracil in RNA (mRNA and tRNA), uracil forms two hydrogen bonds with adenine so the pyrimidine-purine base pairing is maintained.

	Purines always bond with pyrimidines via [[Hydrogen bonds\|hydrogen bonds]] following the [[Chargaff's Rules\|Chargaff rule]] in [[dsDNA\|dsDNA]], more specifically each bond follows [[Watson-Crick base pairing\|Watson-Crick base pairing]] rules<ref name="[3]">Griffiths AJF, Miller JH, Suzuki DT, Lewontin RC, Gelbart WM. Structure of DNA. 2000 [cited 2017 Dec 6]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK21786/</ref>. Therefore adenine specifically bonds to thymine forming two hydrogen bonds, whereas guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. During transcription and [[Translation\|translation]] as thymine is substituted by uracil in RNA (mRNA and tRNA), uracil forms two hydrogen bonds with adenine so the pyrimidine-purine base pairing is maintained.		=== References ===

	~~<br>~~		<references />

	~~<references /><references />~~<references />

170726832 at 05:21, 6 December 2017

2017-12-06T05:21:09Z

← Older revision		Revision as of 05:21, 6 December 2017
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two distinct nitrogenous nucleotide bases which form the five nucleobases present in [[DNA\|DNA]] and RNA<ref name="[1]">Berg JM, Tymoczko JL, Gatto GJ Jr, Stryer L. Biochemistry. W. H. Freeman; 2015.</ref>. Pyrimidine bases are heterocyclic compounds which consist of a single carbon ring containing two nitrogen atoms, whereas purine bases consist of two carbon rings (a pyrimidine ring fused to an [[Imidazole\|imidazole]] ring) containing a greater number of nitrogen atoms, so their structures provide distinct differences splitting nucleobases into two types. There are two types of Purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three types of Pyrimidines: [[Cytosine\|Cytosine]], [[Thymine\|Thymine]] (which is only used in DNA, as its substituted by Uracil in RNA during [[DNA transcription\|transcription]]) and [[Uracil\|Uracil]] (which is only present in types of [[RNA Polymerase II\|RNA]], such as [[MRNA\|mRNA]] and [[TRNA\|tRNA]] substituting Thymine)<ref name="[2]">Alberts B, Johnson A, Lewis J, Morgan D, Raff M, Roberts K, et al. Molecular Biology of the Cell. Garland Publishing; 2014.</ref>.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two distinct [[Nitrogenous_base\|nitrogenous]] nucleotide bases which form the five nucleobases present in [[DNA\|DNA]] and [[RNA\|RNA]]<ref name="[1]">Berg JM, Tymoczko JL, Gatto GJ Jr, Stryer L. Biochemistry. W. H. Freeman; 2015.</ref>. Pyrimidine bases are [[heterocyclic\|heterocyclic]] compounds which consist of a single carbon ring containing two nitrogen atoms, whereas purine bases consist of two carbon rings (a pyrimidine ring fused to an [[Imidazole\|imidazole]] ring) containing a greater number of nitrogen atoms, so their structures provide distinct differences splitting nucleobases into two types. There are two types of Purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three types of Pyrimidines: [[Cytosine\|Cytosine]], [[Thymine\|Thymine]] (which is only used in DNA, as its substituted by Uracil in RNA during [[DNA transcription\|transcription]]) and [[Uracil\|Uracil]] (which is only present in types of [[RNA Polymerase II\|RNA]], such as [[MRNA\|mRNA]] and [[TRNA\|tRNA]] substituting Thymine)<ref name="[2]">Alberts B, Johnson A, Lewis J, Morgan D, Raff M, Roberts K, et al. Molecular Biology of the Cell. Garland Publishing; 2014.</ref>.

	'''Base pairing'''		'''Base pairing'''
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	----		----

	Purines always bond with pyrimidines via [[Hydrogen bonds\|hydrogen bonds]] following the [[Chargaff's Rules\|Chargaff rule]] in dsDNA, more specifically each bond follows [[Watson-Crick base pairing\|Watson-Crick base pairing]] rules<ref name="[3]">Griffiths AJF, Miller JH, Suzuki DT, Lewontin RC, Gelbart WM. Structure of DNA. 2000 [cited 2017 Dec 6]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK21786/</ref>. Therefore adenine specifically bonds to thymine forming two hydrogen bonds, whereas guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. During transcription and [[Translation\|translation]] as thymine is substituted by uracil in RNA (mRNA and tRNA), uracil forms two hydrogen bonds with adenine so the pyrimidine-purine base pairing is maintained.		Purines always bond with pyrimidines via [[Hydrogen bonds\|hydrogen bonds]] following the [[Chargaff's Rules\|Chargaff rule]] in [[dsDNA\|dsDNA]], more specifically each bond follows [[Watson-Crick base pairing\|Watson-Crick base pairing]] rules<ref name="[3]">Griffiths AJF, Miller JH, Suzuki DT, Lewontin RC, Gelbart WM. Structure of DNA. 2000 [cited 2017 Dec 6]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK21786/</ref>. Therefore adenine specifically bonds to thymine forming two hydrogen bonds, whereas guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. During transcription and [[Translation\|translation]] as thymine is substituted by uracil in RNA (mRNA and tRNA), uracil forms two hydrogen bonds with adenine so the pyrimidine-purine base pairing is maintained.

	<br>		<br>

	<references /><references /><references />		<references /><references /><references />

170726832: I added additional content to clearly identify the difference between pyrimidine and purine bases. Moreover I have backed up my content through research, and have specified my references for the information.

2017-12-06T05:17:50Z

I added additional content to clearly identify the difference between pyrimidine and purine bases. Moreover I have backed up my content through research, and have specified my references for the information.

← Older revision		Revision as of 05:17, 6 December 2017
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two ~~building blocks~~ of [[~~Nucleic acids~~\|~~nucleic acids~~]]. There are two types of ~~purines~~: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three ~~different~~ types of ~~pyrimidines~~: [[Cytosine\|~~cytosine~~]], [[Thymine\|~~thymine~~]] and [[Uracil\|~~uracil~~]] (which is only ~~used~~ in [[RNA Polymerase II\|RNA]], [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via [[~~Hydrogen_bonds~~\|hydrogen bonds]]. ~~The purine Adenine forms~~ two hydrogen bonds ~~with the pyrimidine Thymine and the purine Guanine~~ forms three [[Hydrogen bonds\|hydrogen bonds]] with ~~the pyramidine~~ Cytosine. ~~In RNA, mRNA and tRNA, during [[Transcription\|~~transcription]] and [[Translation\|translation]]~~, Thymine~~ is substituted ~~with Uracil meaning Adenine bonds with Uracil instead~~, ~~forming~~ two hydrogen bonds.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two distinct nitrogenous nucleotide bases which form the five nucleobases present in [[DNA\|DNA]] and RNA<ref name="[1]">Berg JM, Tymoczko JL, Gatto GJ Jr, Stryer L. Biochemistry. W. H. Freeman; 2015.</ref>. Pyrimidine bases are heterocyclic compounds which consist of a single carbon ring containing two nitrogen atoms, whereas purine bases consist of two carbon rings (a pyrimidine ring fused to an [[Imidazole\|imidazole]] ring) containing a greater number of nitrogen atoms, so their structures provide distinct differences splitting nucleobases into two types. There are two types of Purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three types of Pyrimidines: [[Cytosine\|Cytosine]], [[Thymine\|Thymine]] (which is only used in DNA, as its substituted by Uracil in RNA during [[DNA transcription\|transcription]]) and [[Uracil\|Uracil]] (which is only present in types of [[RNA Polymerase II\|RNA]], such as [[MRNA\|mRNA]] and [[TRNA\|tRNA]] substituting Thymine)<ref name="[2]">Alberts B, Johnson A, Lewis J, Morgan D, Raff M, Roberts K, et al. Molecular Biology of the Cell. Garland Publishing; 2014.</ref>.

			'''Base pairing'''

			----

			Purines always bond with pyrimidines via [[Hydrogen bonds\|hydrogen bonds]] following the [[Chargaff's Rules\|Chargaff rule]] in dsDNA, more specifically each bond follows [[Watson-Crick base pairing\|Watson-Crick base pairing]] rules<ref name="[3]">Griffiths AJF, Miller JH, Suzuki DT, Lewontin RC, Gelbart WM. Structure of DNA. 2000 [cited 2017 Dec 6]; Available from: https://www.ncbi.nlm.nih.gov/books/NBK21786/</ref>. Therefore adenine specifically bonds to thymine forming two hydrogen bonds, whereas guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. During transcription and [[Translation\|translation]] as thymine is substituted by uracil in RNA (mRNA and tRNA), uracil forms two hydrogen bonds with adenine so the pyrimidine-purine base pairing is maintained.

			<br>

			<references /><references /><references />

Nnjm2: Added some more links.

2016-11-17T20:35:41Z

Added some more links.

← Older revision		Revision as of 20:35, 17 November 2016
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in RNA, [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with the pyrimidine Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with the pyramidine Cytosine. In RNA, mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead, forming two hydrogen bonds.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[RNA Polymerase II\|RNA]], [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via [[Hydrogen_bonds\|hydrogen bonds]]. The purine Adenine forms two hydrogen bonds with the pyrimidine Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with the pyramidine Cytosine. In RNA, mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead, forming two hydrogen bonds.

160349405: Added some text.

2016-11-17T12:28:45Z

Added some text.

← Older revision		Revision as of 12:28, 17 November 2016
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in RNA, [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with the pyrimidine Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with the pyramidine Cytosine. In RNA, mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead, forming two hydrogen bonds.

Nnjm2: Removed image as it was copyrighted.

2016-11-14T15:54:06Z

Removed image as it was copyrighted.

← Older revision		Revision as of 15:54, 14 November 2016
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with ~~U[[Image:2-17.jpg\|right\|300x300px\|The structure of the purines and pyrimidines.]]racil~~ meaning Adenine bonds with Uracil instead.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.

160284704 at 15:39, 14 November 2016

2016-11-14T15:39:47Z

← Older revision		Revision as of 15:39, 14 November 2016
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	[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with ~~Uracil~~ meaning Adenine bonds with Uracil instead.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with U[[Image:2-17.jpg\|right\|300x300px\|The structure of the purines and pyrimidines.]]racil meaning Adenine bonds with Uracil instead.

150440657 at 14:24, 17 October 2016

2016-10-17T14:24:55Z

← Older revision		Revision as of 14:24, 17 October 2016
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	[[Purines\|Purines]] and [[~~pyrimidines~~\|pyrimidines]] are the two building blocks of [[~~nucleic~~ acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[~~cytosine~~\|cytosine]], [[~~thymine~~\|thymine]] and [[~~uracil~~\|uracil]] (which is only used in [[~~mRNA~~\|mRNA]] and [[~~tRNA~~\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine ~~always~~ hydrogen bonds with Thymine and the purine Guanine ~~always~~ [[~~hydrogen~~ bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[~~transcription~~\|transcription]] and [[~~translation~~ \|translation]]~~. ~~Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.		[[Purines\|Purines]] and [[Pyrimidines\|pyrimidines]] are the two building blocks of [[Nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[Cytosine\|cytosine]], [[Thymine\|thymine]] and [[Uracil\|uracil]] (which is only used in [[MRNA\|mRNA]] and [[TRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine forms two hydrogen bonds with Thymine and the purine Guanine forms three [[Hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[Transcription\|transcription]] and [[Translation\|translation]], Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.

Nnjm2 at 13:39, 28 November 2012

2012-11-28T13:39:05Z

← Older revision		Revision as of 13:39, 28 November 2012
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	~~ ~~Purines and pyrimidines are the two building blocks of nucleic acids. There are two types of purines : Adenine and Guanine, and three different types of pyrimidines: cytosine, thymine and uracil (which is only used in mRNA and tRNA). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine always hydrogen bonds with Thymine and the purine Guanine always hydrogen bonds with Cytosine. In mRNA and tRNA, during transcription and translation Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.		[[Purines\|Purines]] and [[pyrimidines\|pyrimidines]] are the two building blocks of [[nucleic acids\|nucleic acids]]. There are two types of purines: [[Adenine\|Adenine]] and [[Guanine\|Guanine]], and three different types of pyrimidines: [[cytosine\|cytosine]], [[thymine\|thymine]] and [[uracil\|uracil]] (which is only used in [[mRNA\|mRNA]] and [[tRNA\|tRNA]]). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine always hydrogen bonds with Thymine and the purine Guanine always [[hydrogen bonds\|hydrogen bonds]] with Cytosine. In mRNA and tRNA, during [[transcription\|transcription]] and [[translation \|translation]]. Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.

120056468 at 13:01, 28 November 2012

2012-11-28T13:01:11Z

← Older revision		Revision as of 13:01, 28 November 2012
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	Purines and pyrimidines are the two building blocks of nucleic acids. There are two types of purines: Adenine and Guanine, and three different types of pyrimidines: cytosine, thymine and uracil (which is only used in mRNA and tRNA). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine always hydrogen bonds with Thymine and the purine Guanine always hydrogen bonds with Cytosine. In mRNA and tRNA, during transcription and translation Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.		Purines and pyrimidines are the two building blocks of nucleic acids. There are two types of purines : Adenine and Guanine, and three different types of pyrimidines: cytosine, thymine and uracil (which is only used in mRNA and tRNA). Purines always bond with pyrimidines via hydrogen bonds. The purine Adenine always hydrogen bonds with Thymine and the purine Guanine always hydrogen bonds with Cytosine. In mRNA and tRNA, during transcription and translation Thymine is substituted with Uracil meaning Adenine bonds with Uracil instead.