Macromolecules

Deoxyribonucleic acid (DNA) is the fundamental molecule of life encoding the genetic code for the development and functioning of every living organism and a large variety of viruses. RNA, proteins, and DNA are the main macromolecules, which are necessary for every form of life. The genetic system is encoded in the form of a sequence of nucleotides (guanine, adenine, thymine, and cytosine), which are denoted by the letters G, A, T, and C. Most DNA molecules consist of double-stranded helices, composed of two long polymers made of simple units named nucleotides, molecules with backbones constructed of alternating sugars (deoxyribose) and phosphate groups (relative of phosphoric acid), with the nucleobases (G, A, T, C) joined to the sugars. DNA is a suitable store for biological information, because the DNA backbone resists cleavage and the double-stranded structure allows the molecule to have a built-in duplicate of the encoded data.
In DNA, the two strands are located in opposite directions to each other. Consequently, these strands are anti-parallel; one backbone is 3' (three prime) and the other 5' (five prime). This presents the direction of the 3rd
In the process of cell division, these chromosomes are duplicated in a process called DNA replication. This process fully furnishes each cell with its full-required set of chromosomes. In eukaryotic organisms (animals, plants, fungi, and protists), most of DNA is stored inside the cell nucleus and partly inside organelles; the examples of the latter are mitochondria or chloroplasts [2]. On the contrary, in prokaryotes (i.e., bacteria), DNA is stored just in the cytoplasm. It should be added that compaction and management of DNA is occurred inside the chromosomes by chromatin proteins such as histones. The interactions between DNA and other proteins are guided by these compact structures, which assist in controlling which parts of the DNA are