DNA

The word “DNA” means the molecule inside almost every living cell that carries genetic instructions, arranged as a double helix of paired bases. In plain terms, the genetic code stored in cells that makes each living thing unique.

“DNA” is pronounced dee-ehn-AY (/ˌdiˌɛnˈeɪ/ in IPA).

Here is “DNA” used in a sentence: “DNA from both parents combines to determine a child's traits.”

Depending on how it is used, “DNA” can be a noun and a verb.

“DNA” is a fairly common word in modern English, usually learned at around the B2 level.

“DNA” has 2 distinct senses listed in this dictionary. The most common is: the molecule inside almost every living cell that carries genetic instructions, arranged as a double helix of paired bases.

DNA stands for deoxyribonucleic acid. It is the long molecule, shaped like a twisted ladder or double helix, that stores the genetic code in nearly every living cell. The name describes its chemistry: a sugar called deoxyribose, phosphate groups, and the nucleic-acid bases that spell out the instructions.

Both are nucleic acids that carry genetic information, but DNA is the stable, double-stranded master copy stored in the cell, while RNA is usually single-stranded and acts as a working messenger that carries instructions from DNA to build proteins. DNA uses the base thymine; RNA uses uracil instead.

DNA is the whole molecule; a gene is a specific segment of it. Each gene is a stretch of DNA that spells out instructions for one particular trait or protein. Think of DNA as an entire instruction manual and genes as the individual instructions written inside it.

DNA carries the instructions that build and run every living thing, and it passes those instructions from parents to offspring, which is why we inherit traits. It also makes each individual genetically unique, so it is used in medicine, ancestry testing, and forensic identification.

DNA is built from four chemical bases — adenine, thymine, guanine and cytosine — attached to a backbone of sugar and phosphate. The bases pair up, A with T and G with C, to form the rungs of the double helix, and their order spells out the genetic code.