What are carbohydrates?





Carbohydrates are polyhydroxy aldehydes and ketones which contain hydrogen and oxygen in the number of standard water (2:1) o r those substances which are converted into polyhydroxy aldehydes and ketones after hydrolysis. Their general formula is Cx(H 2 O)y.

What are major classes of carbohydrates?

There are 3 major classes of carbohydrates which are:

Monosaccharides Polysaccharides Oilgosaccharides

What are monosaccharides?

Monosaccharides are the carbohydrates which cannot be further broken down into simple units by acid hydrolysis e.g. erthyrose, glucose, fructose, etc.

What are oilgosaccharides?

Oilgosaccharides are the carbohydrates which after acid hydrolysis yield two or ten units of monosaccharides per molecule hydrolysed e.g., sucrose, maltose, etc.

What are polysaccharides?

Polysaccharides are the carbohydrates which are formed by natural condensation of a very large number of molecules of monosaccharides e.g., cellulose, starch etc.

What are major functions of carbohydrates?

They are major source of energy. They are used in making structures of cells. They comprise large portions of nucleotides. They play a role in lubrication and immunity.

What are sugars & non-sugars?

Monosaccharides and oligosaccharides are sugars as they are sweet in taste while polysaccharides are not sweet so called as non-sugars.

What is the difference between 'd' & 'l' monosaccharides?

The 'd' monosaccharides are dextrorotatory while 'l' monosaccharides are levorotatory as former rotates the plane-polarized light to right and the latter to left.

What type of isomerism is present in carbohydrates?

Optical isomerism Stereo isomerism Which carbohydrates is obtained from milk?

Lactose.

Define reducing & non-reducing sugars?

Carbohydrates having a free aldehydic or ketonic group are called as reducing sugars while those having no free aldehyde or ketonic group are called non-reducing sygars e.g., sucrose.

What are amino-sugars?

Amino-sugars a hydroxyl group replaced by an amino or acetylamino group e.g., glucosamine and glactosamine.

What is nature of blood-group antigens?

Blood group antigens are specific class of oilgosaccharides that may be bound to proteins or lipids.

Write down any two biochemical reaction of carbohydrates?

Glycolysis, Kreb's Cycle, Pentose phosphate cycle, etc.

Give any two chemical reactions used to confirm the presence of carbohydrates?

Tollen's test, Fehling's test and Molish test.

How are disaccharides taken in diet converted monosaccharides?

As a result of enzymatic hydrolysis.

What is normal concentration of glucose in body?

Normal conc. of glucose in the blood is 60-90mg/100 ml.

How excess glucose is utilized in body?

Excess glucose is converted into fat which is stored in the fat deposits.

What are glycosides?

Alkyl or aryl derivatives of glucose are called as glycosides.







