Bimolecules Part-1 – Important Questions & Preparation Tips

This article talks about important concept, formulae and previous year questions related to Bimolecules. This is very important for UPSEE and WBJEE engineering entrance exam.

Created On: Jan 3, 2017 17:26 IST

In IIT JEE, WBJEE, UPSEE and other engineering entrance examination the chapter Bimolecules plays an important role. About 1-2 questions are being asked from this chapter. This article talks about important concept, formulae and previous year questions related to Bimolecules. The concept given in this article is in concise form and can be used for revision before the examination.


They are the organic molecules that are involved in the maintenance and metabolic processes of living organisms. Thus, they build up the living system and are responsible for their growth and maintenance.

Some of the common biomolecules are:

•    Carbohydrates

•    Proteins

•    Lipids

•    Nucleic acids

•    ATP molecules


On the basis of hydrolysis, carbohydrates are classified as follows:

(a) Monosaccharide

(b) Disaccharides

(c) Polysaccharides

Monosaccharide: These are the simpler carbohydrates which cannot be hydrolysed further to its constituent aldehyde or ketone.

For example glucose,fructose, galactose etc.

UPSEE 2017 Solved Sample Paper Set-1


Disaccharides: It is a sugar which can be hydrolysed into two monosaccharides.

For example sucrose, lactose, maltose.


Polysaccharides: These are carbohydrates which on hydrolysis yield many monosaccharide units.

For example starch, cellulose, glycogen, gums, etc.

Monosaccharides and oligosaccharides are crystalline solids, soluble in water and sweet in taste. These are called sugars. Polysaccharides are amorphous, insoluble in water and tasteless. These are called non-sugars.

D and L configuration of Sugar:

For defining D and L configuration of sugar the compound glyceraldehydes, HOCH2CH(OH)CHO was chosen as the standard.

JEE Main Mathematics Solved Sample Paper Set-VII

d, l glyceraldehyde

Compounds that resembles D-glyceraldehyde at one terminal is known as D-sugar. Similarly, compound that resembles L-glyceraldehyde at one terminal is known as L-sugar.

Note: Natural sugar are D-sugar and synthetic sugar are L-sugar.

Cyclic Structure of Monosaccharides:

Some monosaccharides adopt cyclic structures. This conversion occurs because of the ability of aldehydes and ketones to react with alcohols:

cyclic monosaccharide

 Some questions are given below to test your knowledge.

Q1. Classify the following into monosaccharides and disaccharides.

Ribose, 2-deoxyribose, maltose, galactose, fructose and lactose


Ribose, 2-deoxyribose, galactose, fructose

Disaccharides: -

Maltose, lactose

Q2. Natural sugar is:

(a) D-sugar

(b) L-sugar

(c) Either D or L sugar

(d) None of these


Natural sugar is D-sugar while synthetic sugar is L-sugar.

JEE Main Chemistry Solved Sample Paper Set-VII

Jagran Play
रोमांचक गेम्स खेलें और जीतें एक लाख रुपए तक कैश
ludo_expresssnakes_ladderLudo miniCricket smash
ludo_expresssnakes_ladderLudo miniCricket smash

Related Stories

Comment (0)

Post Comment

7 + 0 =
Disclaimer: Comments will be moderated by Jagranjosh editorial team. Comments that are abusive, personal, incendiary or irrelevant will not be published. Please use a genuine email ID and provide your name, to avoid rejection.