Deoxyribonucleic acid (/diːˈɒksɪˌraɪboʊnjuːˌkliːɪk, -ˌkleɪ-/ (About this soundlisten);[1] DNA) is a molecule composed of two polynucleotide chains that coil around each other to form a double helix carrying genetic instructions for the development, functioning, growth and reproduction of all known organisms and many virusesDNA(DeoxyriboNucleic Acid, 데옥시리보핵산, 디옥시리보 핵산)는 뉴클레오타이드의 중합체인 두 개의 긴 가닥이 서로 꼬여있는 이중나선 구조로 되어있는 고분자화합물이다.[1] 세포 핵에서 발견되어 핵산이라는 이름이 붙게 되었지만 미토콘드리아 DNA와 같이 핵 이외의 세포소기관도 독립된 DNA를 갖고 있는 것이 있다. 보통 소수의 아미노산이 연결된 형태를 펩타이드라 부르고 많은 아미노산이 연결되면 단백질로 부른다 펩티드라는 것은 원래 단백질을 산이나 알칼리와 함께 가열하거나 단백질이 펩신 등의 소화 효소에 의해 소화 분해될 때 생기는 중간 생성물군(群)에 주어진 명칭이었다 Peptides (from Greek language πεπτός, peptós "digested"; derived from πέσσειν, péssein "to digest") are short chains of between two and fifty amino acids, linked by peptide bonds.[1][2] Chains of fewer than ten or fifteen amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A polypeptide is a longer, continuous, unbranched peptide chain of up to approximately fifty amino acids.[3] Hence, peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. A polypeptide that contains more than approximately fifty amino acids is known as a protein.[3][4][5] Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies.[6] Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.[7] All peptides except cyclic peptides have an N-terminal (amine group) and C-terminal (carboxyl group) residue at the end of the peptide (as shown for the tetrapeptide in the image).

 Deoxyribonucleic acid (/diːˈɒksɪˌraɪboʊnjuːˌkliːɪk, -ˌkleɪ-/ (About this soundlisten);[1] DNA) is a molecule composed of two polynucleotide chains that coil around each other to form a double helix carrying genetic instructions for the development, functioning, growth and reproduction of all known organisms and many virusesDNA(DeoxyriboNucleic Acid, 데옥시리보핵산, 디옥시리보 핵산)는 뉴클레오타이드의 중합체인 두 개의 긴 가닥이 서로 꼬여있는 이중나선 구조로 되어있는 고분자화합물이다.[1] 세포 핵에서 발견되어 핵산이라는 이름이 붙게 되었지만 미토콘드리아 DNA와 같이 핵 이외의 세포소기관도 독립된 DNA를 갖고 있는 것이 있다.

보통 소수의 아미노산이 연결된 형태를 펩타이드라 부르고 많은 아미노산이 연결되면 단백질로 부른다

펩티드라는 것은 원래 단백질을 산이나 알칼리와 함께 가열하거나 단백질이 펩신 등의 소화 효소에 의해 소화 분해될 때 생기는 중간 생성물군(群)에 주어진 명칭이었다

Peptides (from Greek language πεπτός, peptós "digested"; derived from πέσσειν, péssein "to digest") are short chains of between two and fifty amino acids, linked by peptide bonds.[1][2] Chains of fewer than ten or fifteen amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides.

A polypeptide is a longer, continuous, unbranched peptide chain of up to approximately fifty amino acids.[3] Hence, peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others.

A polypeptide that contains more than approximately fifty amino acids is known as a protein.[3][4][5] Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies.[6]

Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.[7] All peptides except cyclic peptides have an N-terminal (amine group) and C-terminal (carboxyl group) residue at the end of the peptide (as shown for the tetrapeptide in the image).