Information about Nitrogenous Base
Nitrogenous bases are organic compounds that owe their basic properties to the lone pair of electrons of a nitrogen atom. Typical nitrogenous bases are ammonia (NH3), triethylamine, pyridine, and the nucleobases adenine, guanine, thymine, cytosine, and uracil. Nitrogenous bases can be classified under two groups: purines (A and G) and pyrimidines (C, T, and U). These bases make up a crucial part of both deoxyribonucleotides and ribonucleotides, and the interactions between Adenine/Thymine and Guanine/Cytosine are the basis for the universal genetic code. Uracil replaces Thymine in RNA.
For the structure and list of purines see this link:
For the structure and list of pyrimidines see this link: Chemical structure of thymine Chemical structure of uracil Chemical structure of cytosine
Thymine Uracil Cytosine
Deoxyribonucleic acid (DNA) is the molecule associated with heredity. It is a very long thread-like molecule made up of a very large number of deoxyribonucleotides.
Deoxyribonucleotides are units composed of a base, which can be a pyrimidine base of thymine or cytosine or a purine base of adenine or guanine + a sugar residue which is deoxyribose + a phosphate group. The backbone of the DNA molecule is constant throughout the entire molecule, and consists of the deoxyriboses linked by phosphodiester bridges i.e. the 3'OH group of the sugar of one is linked to the 5'-OH of the next sugar by a phosphate.
The variable part of the DNA is the sequence of the bases, and the precise sequence of the purine and pyrimidine bases carried the genetic information to express the characteristics of the organism. The DNA chain has polarity with one end of the chain having a 5'OH group while the other end has a 3'OH group.
Nitrogenous Bases
Five bases found in nucleic acids. Two purine bases (adenine and guanine) and three pyrimidine bases (cytosine, uracil and thymine). Adenine and guanine occur in both DNA and RNA. Cytosine and thymine are the pair of pyrimidines in DNA, and cytosine and uracil are the pair in RNA. Biological importance of pyrimidines is not restricted to nucleic acids. Vitamin B1 (thiamine) is a pyrimidine derivative, and thiouracil has been successful in the treatment of hyperthyroidisim.
The pyrimidines all display tautomerism. At neutral pH the keto form predominates, but alkaline pH shifts to the enol form. Purines are larger and consist of a six membered pyrimidine ring fused to a 5-membered immidazole ring. A few others occur in nature notably hypoxanthine, xanthine, and uric acid.
Nitrogenous Base There are two families of nitrogenous bases:
Pyrimidine = Nitrogenous base characterized by a six-membered ring made up of carbon and nitrogen atoms. For example: • Cytosine (C)
• Thymine (T) - found only in DNA • Uracil (U) - found only in mRNA.
Purine = Nitrogenous base characterized by a five-membered ring fused to a six-membered ring. For example: • Adenine (A) • Guanine (G)
Adenine is a purine with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine
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Cytosine is one of the five main nucleobases found in the nucleic acids DNA and RNA. It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and
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Deoxyribonucleic acid (DNA) is the molecule associated with heredity. It is a very long thread-like molecule made up of a very large number of deoxyribonucleotides.
Deoxyribonucleotides are units composed of a base, which can be a pyrimidine base of thymine or cytosine or a purine base of adenine or guanine + a sugar residue which is deoxyribose + a phosphate group. The backbone of the DNA molecule is constant throughout the entire molecule, and consists of the deoxyriboses linked by phosphodiester bridges i.e. the 3'OH group of the sugar of one is linked to the 5'-OH of the next sugar by a phosphate.
The variable part of the DNA is the sequence of the bases, and the precise sequence of the purine and pyrimidine bases carried the genetic information to express the characteristics of the organism. The DNA chain has polarity with one end of the chain having a 5'OH group while the other end has a 3'OH group.
Nitrogenous Bases
Five bases found in nucleic acids. Two purine bases (adenine and guanine) and three pyrimidine bases (cytosine, uracil and thymine). Adenine and guanine occur in both DNA and RNA. Cytosine and thymine are the pair of pyrimidines in DNA, and cytosine and uracil are the pair in RNA. Biological importance of pyrimidines is not restricted to nucleic acids. Vitamin B1 (thiamine) is a pyrimidine derivative, and thiouracil has been successful in the treatment of hyperthyroidisim.
The pyrimidines all display tautomerism. At neutral pH the keto form predominates, but alkaline pH shifts to the enol form. Purines are larger and consist of a six membered pyrimidine ring fused to a 5-membered immidazole ring. A few others occur in nature notably hypoxanthine, xanthine, and uric acid.
Nitrogenous Base There are two families of nitrogenous bases:
Pyrimidine = Nitrogenous base characterized by a six-membered ring made up of carbon and nitrogen atoms. For example: • Cytosine (C)
• Thymine (T) - found only in DNA • Uracil (U) - found only in mRNA.
Purine = Nitrogenous base characterized by a five-membered ring fused to a six-membered ring. For example: • Adenine (A) • Guanine (G)
A lone pair is a (valence) electron pair without bonding or sharing with other atoms. They are found in the outermost electron shell of an atom, so lone pairs are a subset of a molecule's valence electrons.
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Electron
Theoretical estimates of the electron density for the first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density
Composition: Elementary particle
Family: Fermion
Group: Lepton
Generation: First
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Theoretical estimates of the electron density for the first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density
Composition: Elementary particle
Family: Fermion
Group: Lepton
Generation: First
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3, 5, 4, 2
(strongly acidic oxide)
Electronegativity 3.04 (Pauling scale)
Ionization energies
(more) 1st: 1402.3 kJmol−1
2nd: 2856 kJmol−1
3rd: 4578.1 kJmol−1
Atomic radius 65 pm
Atomic radius (calc.
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(strongly acidic oxide)
Electronegativity 3.04 (Pauling scale)
Ionization energies
(more) 1st: 1402.3 kJmol−1
2nd: 2856 kJmol−1
3rd: 4578.1 kJmol−1
Atomic radius 65 pm
Atomic radius (calc.
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atom (Greek ἄτομος or átomos meaning "indivisible") is the smallest particle still characterizing a chemical element.
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Ammonia is a compound with the formula NH3. It is normally encountered as a gas with a characteristic pungent odor. Ammonia contributes significantly to the nutritional needs of the planet as a precursor to foodstuffs and fertilizers.
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Triethylamine is the chemical compound with the formula N(CH2CH3)3, commonly abbreviated Et3N. It is a commonly enountered in organic synthesis probably because it is the simplest symmetrically trisubstituted amine, i.e.
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Pyridine is a chemical compound with the formula C5H5N. It is a liquid with a distinctively putrid, fishy odour. Pyridine is a simple and fundamentally important heterocyclic aromatic organic compound that is structurally related to benzene, wherein one CH
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Nucleobases are the parts of RNA and DNA that may be involved in pairing (see also base pairs). These include cytosine, guanine, adenine, thymine (DNA), uracil (RNA) and xanthine and hypoxanthine (mutated forms of guanine and adenine, respectively).
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For the programming language Adenine, see .
Adenine is a purine with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine
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Guanine is one of the five main nucleobases found in the nucleic acids DNA and RNA; the others being adenine, cytosine, thymine, and uracil. With the formula C5H5N5
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5-methyluracil a pyrimidine nucleobase. As the name implies, thymine may be derived by methylation of uracil at the 5th carbon. In RNA thymine is replaced with uracil in most cases.
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Not to be confused with cysteine.
Cytosine is one of the five main nucleobases found in the nucleic acids DNA and RNA. It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and
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Uracil is a pyrimidine which is common and naturally occurring.[1] Uracil was originally discovered in 1900. It was isolated by hydrolysis of yeast nuclein that was found in bovine thymus and spleen, herring sperm, and wheat germ.
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