Nucleic acids, Biology

Nucleic Acids

Friedrich Miescher  (1868) discovered the presence  of these compound  in protoplasm ,but Altman (1889) introduced the term Nucleic acid. These  acids are the largest  and most  complex compounds of carbon, hydrogen, oxygen, nitrogen and phosphorus, and of most biological  importance, two  type of these occur in biological systems viz.

1. Deoxyribonucleic acid (DNA) and

2. Ribonucleic acid (RNA)

Just as proteins and carbohydrates are polymers respectively of amino acid and monosaccharide units or monomers, nucleic acids are long  chain polymers of nucleotide   monomers (polynucleotide's). This polymerization is also dehydration  compensation  process i.e. nucleotide monomers link together by elimination  of water.

Each Nucleotide molecule is itself a complex compound of nitrogenous organic base  a pentose sugar and a phosphoric acid group linked together by dehydration condensation in two steps. First a base  and sugar molecule link by a n glycoside  bond to form a nucleoside. Then the C5 hydroxyl of the sugar molecule of nucleoside joins with a phosphate group to form a nucleotide molecule. Five nitrogenous bases enter into the composition of various nucleotides. these are of 2 kinds pyrimidine  derivatives with a single ring and purine  derivatives  with  a double ring structure. Pyrimidine derivatives are cytosine, Uracil and thymine. Purine derivatives are Adenine and Guanine. The pentose sugars o nucleotides are  also of two type deoxyribose and ribose .thus the nitrogenous bases, combining with pentose sugars and a phosphate group ,form eight types of nucleotide molecules as follows.

(1)   Cytosine + ribose sugar +phosphate = Cytidylic  acid

(2)   Cytosine +deoxyribose sugar +phosphate=Deoxycytidylic acid

(3)   Uracil+ riboxe sugar + phosphate = Uridylic acid

(4)   Thymine +deoxyribose sugar +phosphate= Thymidylic acid

(5)   Adenine + ribose sugar =phosphate=Adenylic acid

(6)   Adenine+ deoxyribose sugar +phosphate = Deoxyadenylic  acid

(7)   Guanine+ ribose sugar + phosphate = Guanuylic acid

(8)   Guanine+ deoxyribose sugar + phosphate= Deoxyguanylic acid

Posted Date: 9/26/2012 6:55:25 AM | Location : United States







Related Discussions:- Nucleic acids, Assignment Help, Ask Question on Nucleic acids, Get Answer, Expert's Help, Nucleic acids Discussions

Write discussion on Nucleic acids
Your posts are moderated
Related Questions
Describe Prematurity in coronaw artery disease ? CAD in Indians tends to be more aggressive and manifests at a younger age. Generally CAD occurring before the age of 55 years i

Q. Categories of value of biodiversity? The value of biodiversity is often divided into two main categories: · UTILITARIAN (also known as instrumental, extrinsic, or use) v

Describe Structure of biological compounds? Structure :  The most important chemical compounds in living systems are probably the organic compounds. The term "organic" in the

Define briefly about the Selenium? The element selenium was discovered in 1817 in association with the element sulphur. However, selenium as an essential nutrient remained unre

Most of the fungi normally observed are members of this group of fungi that includes toadstools, mushrooms and puffballs. This group of fungi is termed as: a) Phycomycetes (pro

what is the cycle of slime moldand thier structure

NE R VE IMPULSE (IT'S GENERATION) - It is an electro chemical phenomenon manifested through ionic movement across cell membrane. It was discovered by A. L. Hodykin & A

OTHE R GLANDS - (i) Mammary glands - Study of mammary gland is mastology. Modified sweat gland. 4-5 pairs in rabbit. 1 pair in human. In opposum 25 pairs (max.).

Q. What is the glycolysis? And what are the products of this process? Glycolysis, the first stage of the aerobic cell respiration is a process in which glucose is degraded brok

Environment impact assessment (EIA) is a tool used for decision making regarding developmental projects and programmes and it may be defined as formal process used to predict the e