Classification and functions of lipids
- 1. Submitted by:-Mayur Pankhi Saikia Department:-Bsc Biotechnology Roll No:-8 College:-Asian Institute of Management and Technology
- 2. ACKNOWLEDGEMENT I would like to express my sincere respect and gratitude to Dr Niren Deka Sir(Principal of Aimt),Dr Monalisha Borah Saikia Mam(HOD of Bioscience Department) and all other faculty members .
- 3. Contents Introduction Definition Functions Classification Bibliography
- 4. INTRODUCTION The word lipid is derived from a greek word “lipos”which means FAT.These are heterogenous group of compounds. Unlike proteins,nucleic acids,polysaccharides,lipids are not polymers rather they are small molecules. They are the chief storage form of energy,besides their role in cellular structure and other biochemical functions.
- 5. DEFINITION Lipids are defined as compounds which are insoluble in water and soluble in organic solvents such as alcohol,ether,chloroform etc. They are the main constituents of plant and animal cells alongwith carbohydrate and protein.
- 6. FUNCTIONS Lipids act as a reservoir of fuel. They are constituents of membranes and regulate membrane permeability. They are source of vitamins(A,D,E &K). They are important as cellular metabolic regulators (steroid hormones and prostaglandins). They protect the internal organs ,serve as insulating materials and give shape and smooth appearance to the body.
- 7. CLASSIFICATION OF LIPIDS Lipids are broadly classified into SIMPLE,COMPLEX,DERIVED and MISCELLANEOUS lipids,which are further subdivided into different categories. SIMPLE LIPIDS:-They are esters of fatty acids with alcohols .They are mainly of two types (a)Fats and oils:-These are esters of fatty acids with glycerol.The difference between fat and oil is only physical.The oil is a liquid while fat is solid at room temperature. (b)Waxes:-Esters of fatty acids with alcohols other than glycerol.These alcohols may be aliphatic or alicyclic.Cetyl alcohol is most commonly found in waxes.
- 8. COMPLEX LIPIDS:-These are esters of fatty acids with alcohols containing additional groups such as phosphate ,nitrogenous bases,carbohydrate etc.They are further divided as follows- (a)PHOSPHOLIPIDS:-They contain phosphoric acid and frequently a nitrogenous base.This is in addition to alcohol and fatty acids. (i)GLYCEROPHOSPHOLIPIDS (ii)SPHINGOPHOSPHOLIPIDS (b)GLYCOLIPIDS:-These lipids contain a fatty acid ,carbohydrate and nitrogenous base.The alcohol is sphingosine ,hence are also called as glycosphingolipids.Glycerol and phosphate are absent.Eg:- cerebrosides,gangliosides. (c)LIPOPROTTEINS:-Macromolecular complexes of lipids with proteins. (d)OTHER COMPLEX LIPIDS:-Sulfolipids ,amino-lipids and lipopolysaccharides are among the other complex lipids.
- 9. DERIVED LIPIDS:-These are the derivatives obtained on the hydrolysis of simple lipids and complex lipids which possess the characteristics of lipids.These include glycerol and other alcohols,fatty acids,mono – and diglycerols,lipidsoluble vitamins ,steroid hormones,hydrocarbons and ketone bodies. MISCELLANEOUS LIPIDS:-These include a large number of compounds possessing the characteristics of lipids.Eg:-carotenoids,squalene terpenes etc. NEUTRAL LIPIDS:-The lipids which are uncharged are referred to as neutral lipids.These are momo-,di- ,triglycerols,cholesterol and cholesteryl esters.
- 10. BIBLIOGRAPHY .Books- Biochemistry by Satyanarayan
- 11. THANK YOU