Question

The difference between amylase and amylopectin is __________.
(a)- $Amylopectin\text{ }have\text{ }1\to 4\alpha -linkage\text{ }and\text{ }1\to 6\beta -linkage$
(b)- $Amylopectin\text{ }have\text{ }1\to 4\alpha -linkage\text{ }and\text{ }1\to 6\alpha -linkage$
(c)- Amylose is made up of glucose and galactose.
(d)- $Amylose\text{ }have\text{ }1\to 4\alpha -linkage\text{ }and\text{ }1\to 6\beta -linkage$

Answer 1

One of the following has the branched-chain structure and one has the linear chain structure. Both of them are made up of glucose components only.

Complete step by step answer:
Starch is not only a single compound but is a mixture of two components-a water-soluble components called amylose (15-20%) and a water-insoluble component called amylopectin (80-85%). The aqueous solution of amylose gives a blue color with an iodine solution. Amylopectin, on the other hand, does not give blue color with iodine solution.
Structure of amylose : It is a linear polymer of $\alpha -D-glu\cos e$ in which${{C}_{1}}$ of one glucose unit is attached to${{C}_{4}}$ of the other through$\alpha -gly\cos idic$ linkage.

Structure of amylopectin: Amylopectin, on the other hand, is a highly branched polymer. It consists of a large number of short chains each containing 20-25 glucose units which are joined together through $\alpha -gly\cos idic$ linkage involving ${{C}_{1}}$ of one glucose unit with${{C}_{4}}$ of the other. The ${{C}_{1}}$of the terminal glucose unit in each chain is further linked to${{C}_{6}}$ of some other glucose unit in the next chain through {{C}_{1}}-{{C}_{6}}$$$$\alpha -gly\cos idic linkage. This gives amylopectin a highly branched structure.

Hence, from the above discussion option (b) is correct.

Note: You may get confused between $\alpha -linkage$ and $\beta -linkage$. $\alpha -linkage$ is formed when the bond is formed on the same side and $\beta -linkage$is formed when the bond is formed between the opposite side.