nucleic acids

Nucleic acids

The cellular molecules DNA and RNA that act as coded instructions for the production of proteins and are copied for transmission of inherited traits.

Mentioned in: Creutzfeldt-Jakob Disease

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nucleic acids [noo-kle´ik]

extremely complex, long-chain compounds of high molecular weight that occur naturally in the cells of all living organisms and constitute the non–amino acid components of nucleoproteins. They form the genetic material of the cell and direct the synthesis of protein within the cell.

Nucleic acids are composed of repeating smaller units, called nucleotides, which are made up of a pentose sugar, a nitrogenous base, and a phosphate group. There are two major classes of nucleic acids: deoxyribonucleic acid (DNA) whose pentose sugar is deoxyribose, and ribonucleic acid (RNA) whose pentose sugar is ribose. The major purine and pyrimidine bases in the nucleic acids are adenine (A), guanine (G), and cytosine (C), which occur in both, and thymine (T) in DNA and uracil (U) in RNA.

RNA is present in both the nucleus and the cytoplasm of many cells. Most of the cytoplasmic RNA is associated with ribosomes, which are the site of protein synthesis. RNA molecules perform several functions in the cell, depending on the type of RNA molecule and its specific properties. DNA is a major constituent of chromosomes in the nuclei of all cells. Its chief function is to provide a genetic message that is encoded in the sequence of bases.

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nucleic acids

threadlike, high-molecular-weight molecules that occur naturally in the cells of all living organisms. They form the genetic material of the cell and direct the synthesis of protein within the cell.

Nucleic acids are composed of repeating smaller units, called nucleotides or bases, which are made up of a pentose sugar, a nitrogenous base, and a phosphate group. There are two major classes of nucleic acids: deoxyribonucleic acid (DNA) whose pentose sugar is deoxyribose, and ribonucleic acid (RNA) whose pentose sugar is ribose. The major purine and pyrimidine bases in the nucleic acids are adenine (A), guanine (G) and cytosine (C), which occur in both, and thymine (T) in DNA and uracil (U) in RNA.

RNA is present in both the nucleus and the cytoplasm of many cells. Most of the cytoplasmic RNA is associated with ribosomes (called rRNA), which are the site of protein synthesis. RNA molecules perform several functions in the cell, depending on the type of RNA molecule and its specific properties. DNA is a major constituent of chromosomes in the nuclei of all cells. Its chief function is to provide a genetic message that is encoded in the sequence of bases.

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nucleic acids acid sequencing

see dna sequencing.