Nucleic acid
Overview
Nucleic acids are biopolymers, or large biomolecules, essential for all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group, and a nitrogenous base. The two main types of nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
Structure and Function
The structures of DNA and RNA are slightly different. DNA is usually a double-stranded molecule with a long chain of nucleotides, while RNA is usually a single-stranded molecule with a shorter chain of nucleotides. DNA stores and transfers genetic information, while RNA directly codes for amino acids and acts as a messenger between DNA and ribosomes to make proteins.
DNA
DNA is a double-stranded molecule that carries the genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses. DNA and RNA are nucleic acids, and, along with proteins and carbohydrates, constitute the three major macromolecules essential for all known forms of life.
Structure
The structure of DNA shows a variety of features that are of interest to the field of biology. The most notable of these is the double helix structure, which was first identified by James D. Watson and Francis Crick in 1953.
Function
The primary function of DNA is to store and transmit the genetic information that tells cells which proteins to make and when to make them.
RNA
RNA is a polymeric molecule essential in various biological roles in coding, decoding, regulation, and expression of genes. Like DNA, RNA is assembled as a chain of nucleotides, but unlike DNA, RNA is found in nature as a single strand folded onto itself, rather than a paired double strand.
Structure
The structure of RNA is a single-stranded molecule made up of nucleotides. The sequence of nucleotides allows RNA to encode genetic information.
Function
RNA carries out a broad range of functions, from translating genetic information into proteins, to regulating gene expression, to maintaining the structure of ribosomes.
Nucleic Acid Synthesis
Nucleic acid synthesis is the process by which nucleotides are synthesized from simpler molecules. The primary function of nucleic acid synthesis is to generate DNA and RNA, which are used in the production of proteins.
Nucleic Acid Sequencing
Nucleic acid sequencing is a technology used to determine the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases—adenine, guanine, cytosine, and thymine—in a strand of DNA.