Question

Differentiate between following :

(i) Amylose and Amylopectin

(ii) Globular protein and Fibrous protein

(iii) Nucleotide and Nucleoside

Answer 1

(i)

	Amylose		Amylopectin
(1)	Amylose is water soluble	(1)	Amylopectin is water insoluble
(2)	Constitutes about 15-20% of starch	(2)	Constitutes about 80-85% of starch
(3)	Long unbranched chain polymer of \(\alpha - D-(+)\) glucose units held together by C1–C4 glycosidic linkage.	(3)	Branched chain polymer of \(\alpha - D-\)glucose units in which chain is formed by C1–C4 glycosidic linkage whereas branching occurs by C1-C6 glycosidic linkage.

 (ii)

	Globular protein		Fibrous protein
(1)	Chains of polypeptides coil around to give a spherical shape.	(1)	Polypeptide chains run parallel and are held together by hydrogen and disulphide bonds. Fibre like structure is formed.
(2)	Soluble in water	(2)	Insoluble in water
(3)	Examples : Insulin, albumins	(3)	Examples : Keratin, myosin

(iii)

Nucleotide	Nucleoside
A unit is formed by attachment of a base, sugar and phosphoric acid.	A unit is formed by attachment of a base and sugar.