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cytosine

cytosine

2 5.7
One of the four bases in DNA and RNA that pairs with guanine
  • noun
  • /ˈsaɪtəˌsiːn/
  • Specialized
translation icon : citosina
  • Genes are identified by the letters AGTC, representing the base chemical nucleotide pairings of Adenine, Guanine, Thymine, and Cytosine.
  • cytosine and guanine

Examples

  • DNA is made of four organic bases adenine, guanine, cytosine, and thymine, or AGC and T.

  • Methylation, or the attachment of a methyl group to DNA at regions where cytosine and guanine are paired ("CpG sites"), has tended to receive the most attention in epigenetic research so far.

    Academic text (2012)
  • So methylation on cytosine would look like this.

  • So these are the bases, thymine, cytosine and uracil, OK.

  • Cytosine, guanine, adenine, and thymine.

  • Bases drifted by: guanine, cytosine, adenine.

    Fiction book (1994)
  • "Notice the sequence is made up of four basic compounds: adenine, thymine, guanine, and cytosine."

    Fiction book (1990)
  • No, the methylation markers are placed down on the cytosine nucleotide using DNA methyl transferase.

  • The test seeks to target a biochemical change called DNA methylation, "which occurs when a chemical group called methyl attaches itself to cytosine, one of the four nucleotides or base building blocks of DNA" (Science and Children, 2009, p. 9).

    Academic text (2011)
  • In DNA, the base cytosine pairs with guanine to form the genetic code.

Synonyms

C
vscytosine
  • Specialized
2 4.6

A DNA and RNA base, cytosine, that pairs with guanine

is the scientific description stressing chemical class and derivation

Surface Forms

cytosine singular
cytosines plural

Morphology

cytosine = cyto + ine

Although built from the combining form 'cyto-' (cell) and the chemical suffix '-ine', the term is a specialised biochemical name whose parts do not help an average B1 learner infer the meaning.

Etymology

The word cytosine comes from the Greek root cyto- from kytos meaning 'cell' or 'container', plus the chemical ending -ine. So cytosine is like a 'cell chemical', which helps explain why it is a base found in the DNA and RNA inside cells.