By definition, Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. To put it in easier terms, DNA, also known as deoxyribonucleic acid, is the makeup of hereditary material in every human and most other organisms as well. The main role of DNA is to store long-term information. DNA carries genetic information, also known as genes. In eukaryotic organisms, such as animals, plants, and fungi, DNA is stored inside the cell’s nucleus. Unlike eukaryotic organisms, prokaryotic organisms store DNA in their cell’s cytoplasm. For the most part, every person’s body has the same DNA.
Inside of the body, the DNA is stored as a code, which is made up of four chemical bases. The four chemical bases are adenine (A), guanine (G), cytosine (C), and thymine (T). These codes are put into different groups to form different types of DNA in different people. There are millions and millions of different combinations that have been discovered by using variations of the four chemical bases.
They form base pairs and each base pair is also attached to a sugar molecule and a phosphate molecule. Together, the base pair, sugar molecule, and phosphate molecule form something called a nucleotide. The nucleotides are then arranged into a complex called a double helix. A nucleotide’s shape resembles a ladder, where the base pairs are the steps and the sugar and phosphate molecules form the sides.
Not only does DNA form nucleotides, but it is also organized into structures called chromosomes. The chromosomes are replicated before the cells divide. This process is called DNA replication. Something you should know about DNA is that it can replicate. The different strands of DNA in the double helix can be duplicated, making two of that same sequence. When cells divide, this is very important because each new cell needs to have a copy of the old cell.
As far as the chemical makeup of DNA goes, it is classified as a long polymer. A DNA is made up of alternating phosphate and sugar residues. The sugar in DNA is 2-deoxyribose, which is a pentose (five-carbon) sugar. The sugars are then joined together by the phosphate groups to form phosphodiester bonds between the third and fifth carbon atoms of adjacent sugar rings. This arrangement is called an antiparallel.
The base pairs adenine and guanine always bond together, as do cytosine and thymine. Unlike in DNA, this is different in RNA. Although uracil isn’t found in DNA, it replaces thymine and pairs with cytosine.