Purpose of Nucleic Acids

The main function of nucleic acids is to store and transmit genetic information and use that information to direct the synthesis of new proteins.

The purpose of nucleic acids is to store and transmit genetic material (the genetic code of an organism) in its molecular form. Nucleic acids also use that molecular information to direct the synthesis of new proteins. The term "nucleic acid" refers to an entire class of dozens of compounds. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are found in all living things, including viruses.

Similarities and Differences of Nucleic Acids

The term "nucleic acid" refers to an entire class of compounds that includes many different types. There are two different types of sugars found in nucleic acids. One is deoxyribose and the other is ribose. The difference is that deoxyribose contains one less oxygen atom than ribose.
Another difference is that the class contains five different kinds of nitrogen bases: adenine (A), cytosine (C), guanine (G), thymine (T), and uracil (U). Deoxyribonucleic acids all contain the first four of the nitrogen bases: A, C, G, and T. Ribonucleic acid only contains the first three (A,C, and G) and uracil (U). It does not contain thymine (T).
Therefore DNA and RNA differ in terms of the sugars they contain and the nitrogen bases that compose them. DNA is the permanent storage location for genetic information and it resides in the form of chromatin in the nucleus of a cell. It controls the synthesis of RNA. In turn, the RNA transmits the genetic information from DNA to the protein-building structures in the cell.

Functions of DNA

DNA is a permanent storage place for genetic information. It contains the complete genetic code for every individual organism. The sequence of nitrogenous bases in DNA determines the protein development in the new cells. DNA synthesizes RNA for the transportation of genetic information to the protein building mechanism in the cell. DNA has a unique molecular structure, the double helix. This formation ensures that no disorders occur. The second identical strand of DNA is a back up in case any of the genetic material is lost or broken down.

General Functions of RNA

RNA is a nucleic acid polymer that works in the transcription of genetic information from DNA into proteins. DNA synthesizes RNA for the transportation of genetic information to the protein synthesizing mechanisms in the cell. In turn, RNA directs the synthesis of new proteins using the genetic information it received from the DNA. Primarily RNA performs as a messenger between DNA and the protein-synthesizing structures known as ribosomes. A form of RNA is also the structural component of the ribosomes that appear as dark granules situated along fibers located in the cellular cytoplasm, which is the fluid that surrounds the cell nucleus.

Types of RNA

Ribonucleic acid functions as a messenger between DNA and the structural protein-synthesis sites known as ribosomes. It forms structural portions of ribosomes, and it serves as a carrier molecule that picks up amino acids from the cytoplasm in the cell and brings them to the ribosomal site of protein synthesis. RNA has three vital functions in protein synthesis and there are three types of RNA that each perform an essential role in the process. The three types are tRNA (transfer RNA), mRNA (messenger RNA) and rRNA (ribosomal RNA).

Functions of mRNA, tRNA and rRNA

DNA is found primarily in the nuclei of cells, but the proteins are made outside of the cell nucleus. Small rRNA (ribosomal RNA) structures located in the cytoplasm of the cell are the sites where the proteins are constructed. The mRNA (messenger RNA) and the tRNA (transfer RNA) read the genetic message from the DNA molecule in the nucleus and carry it out into the cytoplasm to the ribosomes where the message is transformed into proteins.
The first step takes place in the nucleus when a mRNA molecule is created. It is almost identical to the DNA molecule except that it is a single strand whereas the DNA molecule exists as a double helix. The next step is taken when the mRNA moves out of the nucleus into the cytoplasm and attaches itself to a ribosome. The function of tRNA, or the carrier molecules, is to gather the amino acid components of the protein and bring them together at the ribosomes, where they bond together to form proteins. The essential message in the DNA molecule is the sequence of the amino acids in the protein. If this is disrupted, the protein will not function correctly and this can lead to various genetic diseases.

References

• Science Clarified: Biology-Chemistry General Reference
• NetBiochem: Indepth Review of Nucleic Acid Chemistry
• Visionlearning: DNA and RNA Structure and Replication

Resources

• Elmhurst College: Virtual Chembook: Detailed Information and Chemical Diagrams