. Related Products. Related to this Question. Definition:. Which of the following is found in protein, but is not found in DNA? (a) Sulfur (b) Phosphorous (c) Carbon (d) Nitrogen (e) Oxygen. Pseudouridine (abbreviated by the Greek letter psi- Ψ) [1] is an isomer of the nucleoside uridine in which the uracil is attached via a carbon-carbon instead of a nitrogen-carbon glycosidic bond . Pyrimidines are composed of single rings composed of four carbon atoms and two nitrogen atoms. The reason is RNA editing: the alteration of the sequence of nucleotides in the RNA. Vocabulary. It has a role as a prodrug, a human metabolite, a Daphnia magna metabolite, a Saccharomyces cerevisiae. The guanine nucleoside is called guanosine . Thymine is made from uracil in a methylation cycle. premium. It involves copying a gene's DNA sequence to make an RNA molecule. Learn how to say Phosphodiester with EmmaSaying free pronunciation tutorials. Definition guanine: [noun] a purine base C5H5N5O that codes genetic information in the polynucleotide chain of DNA or RNA — compare adenine, cytosine, thymine, uracil. uracil pronunciation. Pronunciation of Cytidine: Learn how to pronounce the word Cytidine. Definition and meaning can be found here:is grouped as a pyrimidine along with cytosine and uracil. Weird things about the name Uracil: The name spelled backwards is Licaru. e. DNA ligase. Each nucleotide that makes up a nucleic acid is comprised of phosphoric acid, sugar (5-carbon), and nucleobase. In RNA, thymine is replaced with uracil. A virus that infects bacteria. Semiconservative replication refers to. When a cell divides, it is important that each daughter cell receives an identical copy of the DNA. a. You'll be able to mark your mistakes quite. Definition. This means that it has a ribose as its sugar constituent with one phosphate group attached. At this time, DNA was also identified as the source of. See uracil meaning in Hindi, uracil definition, translation and meaning of uracil in Hindi. Definition and meaning were removed to avoid copyright violation, but you can find them h. 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). Each nucleotide is made up of a sugar (ribose for nucleotides in RNA, deoxyribose. Ribonucleic acid (RNA) is a molecule that is present in the majority of living organisms and viruses. Examples of how to use “uracil” in a sentence from Cambridge Dictionary. Find uracil similar words, uracil synonyms. In RNA, the base thymine (T) is replaced by the base uracil (___). The sequence of nucleotides in DNA is referred to as the. pyrimidine: [noun] a feeble organic base C4H4N2 of penetrating odor. The guanine nucleoside is called guanosine . RNA is made up of sequence of 4 chemical building. Uracil pronunciation in Australian English Uracil pronunciation in American English Uracil pronunciation in American English Take your English pronunciation to the next level with this audio dictionary references of the word uracil. Discover if uracil is found in DNA. see more. Games. To these enzymes, it does not matter whether thymine or uracil binds to adenine. 4K . It is a component of the combination drug tegafur/uracil. The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Uracil (Lamivudine EP Impurity F) is a nitrogenous base on RNA nucleosides. uracil synonyms, uracil pronunciation, uracil translation, English dictionary definition of uracil. Card 1 of 50. Pyrimidine (C 4 H 4 N 2; / p ɪ ˈ r ɪ. (a) adenine (b) cytosine (c) uracil (d. Uracil är en av pyrimidinbaserna som endast finns i RNA. uracil - Meaning in Odia, what is the meaning of uracil in Odia dictionary, pronunciation, synonyms, usage examples and definitions of uracil in Odia and English. The base-pairing rules are rules that apply during the pairing between one purine and one pyrimidine via tight hydrogen bonds (H-bonds). uracil का हिंदी मतलब और अर्थ। uracil हिन्दी मीनिंग ।uracil ka matlab, uracil ka arthIt could be that RNA used Uracil simply because of Uracil's abundance in nature. or. 2. Thymine (T) is one of the four nucleotide bases in DNA, with the other three being adenine (A), cytosine (C) and guanine (G). The biggest difference is in their shape: DNA is a two-stranded molecule in the form of a double helix. It was isolated from herring sperm and also produced in a laboratory in 1900–1901. Definition. Uracil: Uracil is a pyrimidine base that is a component of RNA. Cytosine ( / ˈsaɪtəˌsiːn, - ˌziːn, - ˌsɪn / [2] [3]) ( symbol C or Cyt) is one of the four nucleobases found in DNA and RNA, along with adenine, guanine, and thymine ( uracil in RNA). Look through examples of uracil translation in sentences, listen to pronunciation and learn grammar. The basic property derives from the lone electron pair on the nitrogen atom. 00:00. What is definition of uracil? Listen to pronunciation. New. An RNA molecule has a backbone made of alternating phosphate groups and the sugar ribose, rather than the deoxyribose found in DNA. It is possible the name you are searching has less than five occurrences per year. 4K . Uracil biosynthetic process Definition: The chemical reactions and pathways resulting in the formation of uracil, 2,4-dioxopyrimidine, one of the pyrimidine bases occurring in RNA, but not in DNA. cytosine b. A hydrogen atom is linked to the 5′-C of the uracil’s aromatic ring structure. It is present in all. Social Security Administration public data, the first name Uracil was not present. Related to this Question. uracil is the translation of "Uracil" into English. It is a member of pyrimidines and a diazine. Our Apps are nice too! Dictionary. adenine: [noun] a purine base C5H5N5 that codes hereditary information in the genetic code in DNA and RNA — compare cytosine, guanine, thymine, uracil. A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base. Discover if uracil is found in DNA. The simplest member of the family is pyrimidine itself, with molecular formula C4H4N2. Adenine (not adenosine) 2. Within a double-stranded DNA molecule, thymine bases on one strand pair with adenine bases on the opposite strand. What is the scientific definition of uracil? Definition of uracil : a pyrimidine base C4H4N2O2 that is one of the four bases coding genetic information in the polynucleotide chain of RNA — compare adenine, cytosine, guanine, thymine. n. Uracil is found in RNA and. The hetero cyclic aromatic structure of the uracil is characterized by the keto groups at carbon-2 and carbon 4. Ultraviolet light may dimerize adjacent cytosine or thymine bases. Understand the definition and structure of the compound uracil. DNA is the genetic material found in all living organisms, ranging from single-celled bacteria to multicellular mammals. Propylthiouracil side effects. RNA is a single-stranded nucleotide chain containing the adenine (A), cytosine (C), uracil (U), and guanine (G) bases. The pyrimidines in DNA are cytosine and thymine; in RNA, they are cytosine and uracil. Samantha. Uracil is among the five nucleobases: adenine, guanine, cytosine, and thymine,but is only found in RNA. nobeastsofierce/Science Photo Library. Understand the definition and structure of the compound uracil. Cytosine 2. Ultraviolet light exposure causes a common DNA mutation where two adjacent thymine molecules form a. Synonyms : U. A uracil-based nucleotide is called uridine. Uracil glycosylase quickly cleaves the uracil residue from the DNA producing an apyrimidinic site. Polymers (Basel) . Definitions of uracil. Uracil is a demethylated form of thymine with the chemical formula C4H4N2O2. They were first described by Dr. A nucleoside is a base linked to a sugar. Learn how to say Phosphodiester with EmmaSaying free pronunciation tutorials. unselfish d. Which base will pair with uracil in RNA? Adenine. It has a pyrimidine ring structure. Understand the definition and structure of the compound uracil. All nucleic acids contain the bases A, C, and G; T, however, is found only in DNA, while U is found in RNA. Depending on the number of phosphates that make up the compound, the ribonucleotide may be designated as monophosphate. Nucleotides are composed of a sugar, a nitrogenous base, and a phosphoric acid. Thymine: Thymine is a pyrimidine base that is a component of DNA. Discover if uracil is found in DNA. A nucleic acid base (or nucleobase) is a nitrogen heterocyclic compound, which serves as the informational monomer of ribonucleic acids (RNA) and deoxyribonucleic acids (DNA), the biopolymers responsible for the storage and transmission of genetic information. DNA is a very long molecule; it is estimated that human DNA is composed of around 3 billion nucleotides. One common use of this strategy is to eliminate amplified DNA and prevent cross-contamination. Adenine and guanine are fused five - and six-membered purines, while cytosine and thymine are six-membered rings called uracil (U), replaces thymine in RNA. Learn how to say Uracil in English correctly with TextToSpeech. Guanine, 1. (Ftorafur, NCI Dictionary)Definition of transformation. Copyright ©. Cytosine is a pyrimidine nucleobase with a chemical formula of C 4 H 5 N 3 O. 3 ′ end (plural 3′ ends) ( biochemistry, genetics) A nucleic acid strand which terminates at the hydroxyl (-OH) chemical group attached to. It under normal conditions is not seen in DNA but is present in RNA replacing thymine. Uracil is a common and naturally occurring pyrimidine nucleobase in which the pyrimidine ring is substituted with two oxo groups at positions 2 and 4. The term «uracil» is regularly used and occupies the position in our list of most widely used terms in the English dictionary. from . More than 50 mutations in the DPYD gene have been identified in people with dihydropyrimidine dehydrogenase deficiency. A phosphate group attached to the 3' carbon of one ribose molecule attaches to the 5' carbon of the next ribose molecule. [2] uracil: [ u´rah-sil ] a pyrimidine base found in ribonucleic acid (RNA). Uracil - Meaning in Hindi. A nucleotide is composed of a nitrogenous base, deoxyribose (five-carbon sugar), and at least one phosphate group. C. US English. Why is uracil used in RNA? Uracil is energetically less expensive for the production of thymine. URACIL definition: a pyrimidine present in all living cells , usually in a combined form, as in RNA. It is made up of nucleotides, which are ribose sugars attached to nitrogenous bases and phosphate groups. Abbr. Press and start speaking. | Meaning, pronunciation, translations and examples in American English Uracil definition: A colorless, crystalline, pyrimidine base, C 4 H 4 N 2 O 2 , that occurs as a constituent of RNA. a base containing nitrogen that is found in RNA (but not in DNA) and derived from pyrimidine; pairs with adenine. Activity is measured by release of [3 H]-uracil in a 50 μl Standard Taq Reaction Buffer containing 0. Learn the function of uracil, as well as its properties. RNA Adenine will also pair with DNA’s Thymine, and DNA Adenine will pair with RNA’s Uracil. Base pairs refer to the sets of hydrogen-linked nucleobases that make up nucleic acids DNA and RNA. 3. It is found in the nucleus of eukaryotes and in the organelles, chloroplasts, and mitochondria. The nitrogenous bases are purines such as adenine (A) and guanine (G), or pyrimidines such as cytosine (C), thymine (T), and uracil (U). Uracil-DNA Glycosylase, heat-labile contains the equally named enzyme found in the marine bacterium BMTU 3346. Tegafur is converted to fluorouracil by the CYP isoenzymes, and uracil prevents further degradation by competitive inhibition of dihydropyrimidine dehydrogenase [2 R]. : a pyrimidine base C4H4N2O2 that is one of the four bases coding genetic information in the polynucleotide chain of RNA compare adenine, cytosine, guanine, thymine. RNA consists of ribose nucleotides (nitrogenous bases appended to a ribose sugar) attached by phosphodiester bonds, forming strands of varying lengths. With the formula C 5 H 5 N 5 O, guanine is a derivative of purine. Mark. A) nitrogenous bases B) a repeating sugar-nucleotide-sugar-nucleotide pattern C) a repeating sugar-phosphate-sugar. Understand the definition and structure of the compound uracil. Chapter 11 / Lesson 9. uracil noun grammar (chemistry) One of the bases of RNA. Tegafur is a chemotherapeutic prodrug of 5-fluorouracil (5-FU) used in the treatment of cancers. noun. Nucleotide Definition. Molecular Formula. Thymine. Tags for the entry "uracil" What uracil means in Punjabi, uracil meaning in Punjabi, uracil definition, explanation, pronunciations and examples of uracil in Punjabi. B. The structure of uracil can be described as. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. 4K . Record yourself saying 'uracil' in full sentences, then watch yourself and listen. Tags for the word Uracil: Hindi meaning of Uracil, What Uracil means in hindi, Uracil meaning in hindi, hindi mein Uracil. a single ring. WordSense Dictionary: uracil - spelling, hyphenation, synonyms, translations, meanings & definitions. It has adenine, thymine, Guanine and Cytosine, where adenine pairs up with thymine and guanine pairs up with cytosine, in case of RNA, thymine is replaced. (YOOR-uh-sil) A chemical compound that is used to make one of the building blocks of RNA. Learn how to say Uracil with EmmaSaying free pronunciation tutorials. Examples of how to use “uracil” in a sentence from the Cambridge Dictionary LabsUracil: Definition & Structure. Definition of thymine noun in Oxford Advanced Learner's Dictionary. Unit Definition One unit is defined as the amount of enzyme that catalyzes the release of 60 pmol of uracil per minute from double-stranded, uracil-containing DNA. Spontaneous hydrolysis of cytosine changes it to a uracil. 11. Thymine (T) is one of the four nucleotide bases in DNA, with the other three being adenine (A), cytosine (C) and guanine (G). Uracil. Chapter 11 / Lesson 9. It has only one phosphate group attached to the. Interestingly, clear differences were shown between the uracil enrichment patterns induced by the two drugs. Uracil like other pyrimidines is an aromatic heterocyclic compound with a pyrimidine ring that comprises alternating nitrogen and carbon atoms. A) nucleotide B) carbohydrate C) fatty acid D) amino acid, The backbone of DNA consists of _____. Formula: C4H4N2O2 0. Like the UNG from E. How to say Thymine in English? Pronunciation of Thymine with 3 audio pronunciations, 2 synonyms, 12 translations and more for Thymine. This base pairing is necessary for the stability and folding of RNA molecules, and recognition of RNA sequences. Pick your prefered accent: Alex. Related to this Question. A simple adenine definition is a chemical compound used to make the nucleotide building blocks of DNA and RNA as well as substances that store and provide energy for cells. The sequence of the four nucleotide bases encodes DNA’s information. The structure of DNA. Norton and Company, Inc. What is Uracil. What is the correct order of steps. One of the bases of RNA. Uracil: Uracil only occurs in RNA. Etymology: The term “thymine” is derived from the Greek word “thumos,” meaning “spirit” or “soul,” due to its association with thymus glands. There are three major types of RNA involved in this process: (1) messenger RNA (mRNA), (2) transfer RNA (tRNA), and (3) ribosomal RNA (rRNA). It has a role as a metabolite, a human metabolite, an Escherichia coli metabolite and a mouse metabolite. In nucleic acids, it. Auxotroph refers to any microorganism that has lost the ability to synthesize an organic compound required for its growth, usually as a result of. It also has one ring of carbon, which makes it a pyrimidine. RNA editing occurs by two distinct mechanisms: Substitution Editing: chemical alteration of individual nucleotides (the equivalent of point mutations). Uracil is one of the nucleobases in the RNA, such as adenine, Guanine and cytosine where as in all living beings that contains DNA, lack uracil in its nucleotide base pairs. ” In DNA, A and T pair. Nucleosides are components of. DNA and RNA. Understand the definition and structure of the compound uracil. uracil noun. Transcription is the first step in gene expression. How would you pronounce Uracil?What is uracil in English? Pronunciation, translation, synonyms, examples, rhymes, definitions of uracil in English. Chapter 11 / Lesson 9. This can account for its utilization in RNA. Uracil is a demethylated form of thymine . It has a pyrimidine ring structure. In RNA, the nucleotide thymine is replaced with _____. Thymine and uracil are distinguished by merely the presence or absence of a. Definition. : 250 The other diazines are pyrazine (nitrogen atoms at the. from . The molecular formula of uracil is C 4 H 4 N 2 O 2, while the molecular formula of uridine is C. How to say Fluorouracil in English? Pronunciation of Fluorouracil with 1 audio pronunciation and more for Fluorouracil. Noun [ edit] uracilo m (plural uracilos) ( organic chemistry) uracil. Nucleotides can be further broken down to a. A Dictionary of Nursing. Uracil-DNA Glycosylase, heat-labile contains the equally named enzyme found in the marine bacterium BMTU 3346. Pyrimidine is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Thymine: Thymine only occurs in DNA. A pyrimidine is an organic compound known as an aromatic heterocyclic compound and has the molecular formula of C 4 H 4 N 2. thymine c. You can hear the audio and see the cursor moving across the signal below. Sample translated sentence: In RNA, thymine is replaced by uracil (U). A nucleic acid is a biopolymer composed of monomeric units of nucleotides. Definition. , 5-methyl-uracil) and (B) de novo biosynthesis of dTMP. Uracil is planar and unsaturated and has the ability to absorb light. Pronunciation of Cytidine: Learn how to pronounce the word Cytidine. Thymine is one of the four nitrogenous nucleobases that form the basic building blocks of deoxyribonucleic acid (DNA). Abbr. Also called: 5-methyl uracil. Translation. haɪˈdrɒksɪl. Dotted lines show hydrogen bonds. Uracil: Definition & Structure. Name the four nitrogenous bases that are found in DNA. It pairs with the adenine through hydrogen bonds. The RNA molecule consists of a sequence of nucleotides, each containing a five-carbon sugar (ribose), a phosphate group, and a nitrogenous base. Within a double-stranded DNA molecule, thymine bases on one strand pair with adenine bases on the opposite strand. Understand the definition and structure of the compound uracil. a purine base found in DNA and RNA. Pyrimidine bases are weakly basic. Related to this Question. James Watson who are best known for discovering the helical, “twist around,” structure of DNA (1953). The replication of DNA occurs during the synthesis phase, or S phase, of the cell cycle, before the cell enters mitosis or meiosis. Become a Study. (Wikipedia)Uracil 释义: a pyrimidine present in all living cells , usually in a combined form, as in RNA. Thymine (not thiamine, not thymidine), Base + sugar and more. e. WikiMatrix Magkakaiba rin ang mga posibleng nitrohenong beis na makikita sa dalawang klase ng asido nukleiko: adenine, cytosine, at guanine ay posible sa RNA at DNA, subalit ang thymine ay posible lamang sa DNA at ang uracil ay posible. Found in RNA, it base pairs with adenine and replaces thymine during DNA transcription. The five nucleosides are commonly. Uracil is similar to thymine in terms of structure except for the methyl group at position 5 in the heterocyclic aromatic ring present in thymine. Pick your prefered accent: Alex. How to say acetylation in English? Pronunciation of acetylation with 2 audio pronunciations, 3 synonyms, 2 meanings, 14 translations, 1 sentence and more for acetylation. A nitrogenous base is an organic molecule that contains the element nitrogen and acts as a base in chemical reactions. e. Yes, RNA always contains uracil as a base nucleotide that pairs with adenine in place of the thymine nucleotide. noun. . Last updated. To learn more about thymine, review the accompanying lesson on Thymine: Structure & Definition. Definition: A nucleic acid that contains the genetic instructions used in the development and functioning of all modern living organisms. Have we pronounced this wrong? Teach everybody how you say it using the comments below!!Looking for help to learn English? Claim top deals on the best Englis. A. Both uridine and uracil are essential components of RNA. Investigation of DNA damage, repair, and epigenetic base modifications became a rapidly developing scientific field, especially in the last decade, fed by numerous new technical solutions such as a new generation of DNA sequencing approaches [72,73]. You should be able to mark your mistakes quite easily. Answer and Explanation: 1. Cytosine forms a component of nuclei acids in form of nucleoside or nucleotide and has a melting point of 320-325 °C. The other nucleotide that can bond with adenine is thymine. Thus, adenine complementary base pairs with uracil in RNAs. Etymology: “ nucleo “- (“nucleus”) + – ide (chemical suffix). View this answer. Uracil: Definition & Structure. Pseudouridine is the most abundant RNA modification in cellular RNA. SHABDKOSH Apps. uracil d. URACIL definition: a pyrimidine present in all living cells , usually in a combined form, as in RNA. Record yourself saying 'uracil' in full sentences, then watch yourself and listen. Uracil is only present in RNA molecules, while thymine is only present in. fluorouracil ( countable and uncountable, plural fluorouracils) ( pharmacology) A fluorine - substituted derivative of uracil C 4 H 3 FN 2 O 2 which inhibits DNA synthesis and is used as a chemotherapy drug in the treatment of cancer. In this article, we will explore the difference between uracyl and uracil and clarify which one is. Occurrence. Return to Modified Bases Modifications. Study with Quizlet and memorize flashcards containing terms like DNA and RNA are polymers composed of _____ monomers. Spoken pronunciation of uracil in English and in Tamil. Uracil-ftorafur is a combination of tegafur, an oral prodrug of fluorouracil, and uracil in a 1:4 molar ratio. 2 μg DNA (10 4 –10 5 cpm/μg) in 30 minutes at 37°C. In DNA and RNA, cytosine. U A pyrimidine base, C4H4N2O2, that is an. US English. When base pairing with adenine, uracil acts as both a hydrogen bond acceptor and a hydrogen bond donor. This is accomplished by the process of DNA replication. RNA contains the nucleotides adenine, guanine, cytosine and uracil (U). Origin and meaning of name Adenine. audio files are free to play or download. 3. The bases used in DNA are adenine (A), cytosine (C), guanine (G) and thymine (T). L'uracile est une base azotée de type pyrimidine comme la thymine et la cytosine. You'll be able to mark your mistakes quite. DNA is the genetic material found in living. Uracil: Definition & Structure. It pairs with adenine and is symbolised by U. noun. ura· cil ˈyu̇r-ə-ˌsilUracil like other pyrimidines is an aromatic heterocyclic compound with a pyrimidine ring that comprises alternating nitrogen and carbon atoms. Pyrimidines- Cytosine (C), Thymine (T; found only in DNA), Uracil (U; found only in RNA) Pentose sugar : There are two types of pentose sugars: Deoxyribose sugar (found only in DNA)Definition. Den innehåller två ketogrupper vid C-2 och C-4 i dess heterocykliska pyrimidinring. How to properly pronounce uracil? uracil Pronunciation ˈyʊər ə sɪl uracil Here are all the possible pronunciations of the word uracil. However, while RNA is transcribed using only these four bases, they are. uracil noun. During DNA replication, uracil will pair with adenine rather than guanine (as it would if the base was still cytosine), so an uncorrected cytosine-to. uracil: ChEBI ID CHEBI:17568: Definition A common and naturally occurring pyrimidine nucleobase in which the pyrimidine ring is substituted with two oxo groups at positions 2 and 4. | Meaning, pronunciation, translations and. creating new combinations of alleles. Chapter 11 / Lesson 9. one of the nitrogen-containing bases (see pyrimidine) occurring in the nucleic acid RNA. A) Cytidine is deaminated to uracil so it would be difficult for any repair mechanism to differentiate between uracil that belongs in the sequence and uracil that resulted. DNA pairing is A,T and C,G which is Adenine and Thymine and Guanine and Cytosone. Transcription uses one of the two exposed DNA. See examples of. Heterocyclic compounds are stable, ring-shaped compounds in which not. before it is translated into protein. from . These rules apply to both types of double-stranded nucleic acids, particularly, double-stranded DNA as well as double-stranded RNA (with an exception of A = T in. 4K . Figure 1. Uracil is similar to thymine in terms of. Sample translated sentence: Nukleotid u RNK, ali ne i DNK je uracil? ↔ The nucleotide in RNA but not DNA- -. It is a component of the combination drug tegafur/uracil. Definition. Uracil-DNA glycosylase (UDG) is a highly conserved repair enzyme that catalyzes the excision of uracil from uracil-containing single- and double-stranded DNA 1,2,3,4,5,6,7. See more. Symbol. RNA (ribose nucleic acid) is a complex molecule that plays a big part in living cells. US English. It is a part of both nucleosides and a nucleotide. Definition: Gene. Understand the definition and structure of the compound uracil. e. Video shows what uracil means. a sugar that is a constituent of nucleic acids. It is found in the nucleus of eukaryotes and in the organelles, chloroplasts, and mitochondria. The nitrogenous bases in RNA are adenine, guanine, cytosine, and uracil, which replaces thymine in DNA. A nitrogenous base (also called nucleobase) is a nitrogen-containing compound that may form a nucleoside when they are attached to a five-carbon sugar ribose or deoxyribose. Heterocyclic compounds are stable, ring-shaped compounds in which not. Molecular Formula. DNA and RNA. Uracil was identified in the sample returned from the asteroid Ryugu. adenine: [noun] a purine base C5H5N5 that codes hereditary information in the genetic code in DNA and RNA — compare cytosine, guanine, thymine, uracil.