Cytosine /ˈsaɪtɵsɨn/ (C) is one of the four main bases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at position 2). The nucleoside of cytosine is cytidine. In Watson-Crick base pairing, it forms three hydrogen bonds with guanine.

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  • 1. [Thymine] Thymine /ˈθaɪmɨn/ (T, Thy) is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. In RNA, thymine is replaced by the nucleobase uracil.
  • 2. [Guanine] Guanine /ˈɡwɑːnɨn/ (G, Gua) is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine (uracil in RNA). In DNA, guanine is paired with cytosine. With the formula C5H5N5O, guanine is a derivative of purine, consisting of a fused pyrimidine-imidazole ring system with conjugated double bonds. Being unsaturated, the bicyclic molecule is planar. The guanine nucleoside is called guanosine.
  • 3. [Adenine] Adenine /ˈædɨnɨn/ (A, Ade) is a nucleobase (a purine derivative) 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 dinucleotide (NAD) and flavin adenine dinucleotide (FAD), and protein synthesis, as a chemical component of DNA and RNA. The shape of adenine is complementary to either thymine in DNA or uracil in RNA.
  • 4. [Uracil] Uracil /ˈjʊərəsɪl/ (U) is one of the four nucleobases in the nucleic acid of RNA that are represented by the letters A, G, C and U. The others are adenine (A), cytosine (C), and guanine (G). In RNA, uracil binds to adenine via two hydrogen bonds. In DNA, the uracil nucleobase is replaced by thymine. Uracil could be considered a demethylated form of thymine.
  • 5. [Pyrimidine] Pyrimidine is an aromatic heterocyclic organic compound similar to pyridine. One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has the nitrogens at positions 1 and 3 in the ring. The other diazines are pyrazine (nitrogens 1 and 4) and pyridazine (nitrogens 1 and 2). In nucleic acids, three types of nucleobases are pyrimidine derivatives: cytosine (C), thymine (T), and uracil (U).
  • 6. [5-Methylcytosine] 5-Methylcytosine is a methylated form of the DNA base cytosine that may be involved in the regulation of gene transcription. When cytosine is methylated, the DNA maintains the same sequence, but the expression of methylated genes can be altered (the study of this is part of the field of epigenetics). 5-Methylcytosine is incorporated in the nucleoside 5-methylcytidine.
  • 7. [Nucleoside] Nucleosides are glycosylamines that can be thought of as nucleotides without a phosphate group. A nucleotide is composed of a nucleobase (also termed a nitrogenous base), a five-carbon sugar (either ribose or deoxyribose), and one or more phosphate groups while a nucleoside consists simply of a nucleobase and a 5-carbon sugar. In a nucleoside, the
  • 8. [Base pair] Base pairs, which form between specific nucleobases (also termed nitrogenous bases), are the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, Watson-Crick base pairs (guanine-cytosine and adenine-thymine) allow the DNA helix to maintain a regular helical structure that is
  • 9. [Nucleotide] Nucleotides are organic molecules that serve as the monomers, or subunits, of nucleic acids like DNA and RNA. The building blocks of nucleic acids, nucleotides are composed of a nitrogenous base, a five-carbon sugar (ribose or deoxyribose), and at least one phosphate group.
  • 10. [DNA methyltransferase] In biochemistry, the DNA methyltransferase (DNA MTase) family of enzymes catalyze the transfer of a methyl group to DNA. DNA methylation serves a wide variety of biological functions. All the known DNA methyltransferases use S-adenosyl methionine (SAM) as the methyl donor.
  • 11. [Point mutation] A point mutation, or single base substitution, is a type of mutation that causes the replacement of a single base nucleotide with another nucleotide of the genetic material, DNA or RNA. The term point mutation also includes insertions or deletions of a single base pair.
  • 12. [DNA repair] DNA repair is a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human cells, both normal metabolic activities and environmental factors such as UV light and radiation can cause DNA damage, resulting in as many as 1 million individual molecular lesions per cell
  • 13. [Methylation] In the chemical sciences, methylation denotes the addition of a methyl group to a substrate or the substitution of an atom or group by a methyl group. Methylation is a form of alkylation with a methyl group, rather than a larger carbon chain, replacing a hydrogen atom. These terms are commonly used in chemistry, biochemistry, soil science, and the biological sciences.
  • 14. [Cytidine] Cytidine is a nucleoside molecule that is formed when cytosine is attached to a ribose ring (also known as a ribofuranose) via a β-N1-glycosidic bond. Cytidine is a component of RNA.
  • 15. [Deamination] Deamination is the removal of an amine group from a molecule. Enzymes that catalyse this reaction are called deaminases.
    In the human body, deamination takes place primarily in the liver, however glutamate is also deaminated in the kidneys. Deamination is the process by which amino acids are broken down if there is an excess of protein
  • 16. [RNA] Ribonucleic acid (RNA) is a family of large biological molecules that perform multiple vital roles in the coding, decoding, regulation, and expression of genes. Together with DNA, RNA comprises the nucleic acids, which, along with proteins, constitute the three major macromolecules essential for all known forms of life. Like DNA, RNA is assembled as a
  • 17. [5-Hydroxymethylcytosine] 5-Hydroxymethylcytosine is a DNA pyrimidine nitrogen base. It is formed from the DNA base cytosine by adding a methyl group and then a hydroxy group. It is important in epigenetics, because the hydroxymethyl group on the cytosine can possibly switch a gene on and off. It was first seen in bacteriophages in 1952. However, in
  • 18. [Cytidine triphosphate] Cytidine triphosphate is a pyrimidine nucleoside triphosphate.
    CTP is a substrate in the synthesis of RNA.
    CTP is a high-energy molecule similar ATP, but its role as an energy coupler is limited to a much smaller subset of metabolic reactions. CTP is a coenzyme in metabolic reactions like the synthesis of glycerophospholipids and glycosylation of proteins.
  • 19. [APOBEC] APOBEC ("apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like") is a family of evolutionarily conserved proteins.
    A mechanism of generating protein diversity is mRNA editing. Members of this family are C-to-U editing enzymes. The N-terminal domain of APOBEC like proteins is the catalytic domain, while the C-terminal domain is a pseudocatalytic domain. More specifically, the catalytic domain
  • 20. [Heterocyclic compound] A heterocyclic compound is a cyclic compound that has atoms of at least two different elements as members of its ring(s). The counterparts of heterocyclic compounds are homocyclic compounds, the rings of which are made of a single element.
  • 21. [DNA] Deoxyribonucleic acid (DNA) is a molecule that encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses. DNA is a nucleic acid; alongside proteins and carbohydrates, nucleic acids compose the three major macromolecules essential for all known forms of life. Most DNA molecules consist of two biopolymer
  • 22. [Albrecht Kossel] Ludwig Karl Martin Leonhard Albrecht Kossel (16 September 1853 – 5 July 1927) was a German biochemist and pioneer in the study of genetics. He was awarded the Nobel Prize for Physiology or Medicine in 1910 for his work in determining the chemical composition of nucleic acids, the genetic substance of biological cells.
  • 23. [Aromatic hydrocarbon] An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with alternating double and single bonds between carbon atoms forming rings. The term 'aromatic' was assigned before the physical mechanism determining aromaticity was discovered; the term was coined as such simply because many of the compounds have a sweet or pleasant odor. The
  • 24. [Adenosine triphosphate] Adenosine triphosphate (ATP) is a nucleoside triphosphate used in cells as a coenzyme.
    It is often called the "molecular unit of currency" of intracellular energy transfer. ATP transports chemical energy within cells for metabolism. It is one of the end products of photophosphorylation, cellular respiration, and fermentation and used by enzymes and structural proteins in many
  • 25. [Adenosine diphosphate] Adenosine diphosphate, abbreviated ADP, is an important organic compound in metabolism and is essential to the flow of energy in living cells. A molecule of ADP consists of three important structural components: a sugar backbone attached to a molecule of adenine and two phosphate groups bonded to the 5' carbon atom of ribose. The carbon
  • 26. [Amine] Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines, trimethylamine, and aniline; see Category:Amines for a list of amines. Inorganic derivatives of ammonia are also called amines, such as chloramine (NClH2); see Category:Inorganic amines.
  • 27. [Hydroxylation] Hydroxylation is a chemical process that introduces a hydroxyl group (-OH) into an organic compound. In biochemistry, hydroxylation reactions are often facilitated by enzymes called hydroxylases. Hydroxylation is the first step in the oxidative degradation of organic compounds in air. It is extremely important in detoxification since hydroxylation converts lipophilic compounds into water-soluble (hydrophilic) products that are more readily excreted. Some drugs (e.g. steroids) are activated or deactivated by hydroxylation.
  • 28. [Deutsch–Jozsa algorithm] The Deutsch–Jozsa algorithm is a quantum algorithm, proposed by David Deutsch and Richard Jozsa in 1992 with improvements by Richard Cleve, Artur Ekert, Chiara Macchiavello, and Michele Mosca in 1998. Although of little practical use, it is one of the first examples of a quantum algorithm that is exponentially faster than any possible deterministic classical algorithm. It is also a deterministic algorithm, meaning that it always produces an answer, and that answer is always correct.
  • 29. [Thymus] The thymus is a specialized organ of the immune system. Within the thymus, T-cells mature.
    T cells are critical to the adaptive immune system, where they adapt specifically to foreign invaders. Each T cell attacks a specific foreign substance which it identifies with its receptor. T cells have receptors which are generated by randomly shuffling gene
  • 30. [Nuclear magnetic resonance] Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a magnetic field absorb and re-emit electromagnetic radiation. This energy is at a specific resonance frequency which depends on the strength of the magnetic field and the magnetic properties of the isotope of the atoms; in practical applications, the frequency is similar to
  • 31. [Enzyme] Enzymes /ˈɛnzaɪmz/ are large biological molecules responsible for the thousands of metabolic processes that sustain life. They are highly selective catalysts, greatly accelerating both the rate and specificity of metabolic reactions, from the digestion of food to the synthesis of DNA. Most enzymes are proteins, although some catalytic RNA molecules have been identified. Enzymes adopt a specific three-dimensional structure, and may employ organic (e.g. biotin) and inorganic (e.g. magnesium ion) cofactors to assist in catalysis.
  • 32. [Ketone] In chemistry, a ketone (alkanone) /ˈkiːtoʊn/ is an organic compound with the structure RC(=O)R', where R and R' can be a variety of carbon-containing substituents. Ketones and Aldehydes are simple compounds that contain a carbonyl group (a carbon-oxygen double bond). They are considered "simple" because they don't have reactive groups like -OH or -Cl attached
  • 33. [David Deutsch] David Elieser Deutsch, FRS (born 1953) is a British physicist at the University of Oxford. He is a non-stipendiary Visiting Professor in the Department of Atomic and Laser Physics at the Centre for Quantum Computation (CQC) in the Clarendon Laboratory of the University of Oxford. He pioneered the field of quantum computation by formulating a
  • 34. [Qubit] In quantum computing, a qubit (/ˈkjuːbɪt/) or quantum bit is a unit of quantum information—the quantum analogue of the classical bit.  A qubit is a two-state quantum-mechanical system, such as the polarization of a single photon: here the two states are vertical polarization and horizontal polarization.  In a classical system, a bit would have to
  • 35. [Quantum] In physics, a quantum (plural: quanta) is the minimum amount of any physical entity involved in an interaction. Behind this, one finds the fundamental notion that a physical property may be "quantized," referred to as "the hypothesis of quantization". This means that the magnitude can take on only certain discrete values.
  • 36. [Information] Information (shortened as info or info.) is that which informs, i.e. that from which data can be derived. Information is conveyed either as the content of a message or through direct or indirect observation of some thing. That which is perceived can be construed as a message in its own right, and in that sense,
  • 37. [Quantum computer] A quantum computer is a computation device that makes direct use of quantum-mechanical phenomena, such as superposition and entanglement, to perform operations on data. Quantum computers are different from digital computers based on transistors. Whereas digital computers require data to be encoded into binary digits (bits), each of which is always in one of two
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