Carbohydrates constitute an important class of compounds like glucose, fructose, sucrose, starch, cellulose, etc., which play a vital role in our everyday life. They are the ultimate source of most of our food. We clothe ourselves with cellulose in the form of cotton; rayon and linen. We build furniture and houses from cellulose in the form of wood. Thus, carbohydrates provide us with basic necessities of life, food, clothing and shelter.
Carbohydrates are also known as saccharides. Originally, the name carbohydrate was given to the compounds pertaining to general formula Cx(H2O)y, and they were considered to be hydrates of carbon. However, this definition could not hold ground for long because many compounds like formaldehyde (CH2O), acetic acid (C2H4O2), etc., conform to formula Cx(H2O)y but they do not exhibit the characteristic properties of carbohydrates.
According to the modem definition carbohydrates are defined as polyhydroxy aldehydes or polyhydroxy ketones or the compounds that yield such compounds on hydrolysis.
After studying this unit, the students will be able to
- identify the sources and properties of carbohydrates
- describe the nomenclature and structure of carbohydrates
- describe carbohydrate as a polymer
- describe the uses of carbohydrates