Chapter 20, Problem 20.20UKC

During the digestion of starch from potatoes, the enzyme α-amylase catalyzes the hydrolysis of starch into maltose. Subsequently, the enzyme maltase catalyzes the hydrolysis of maltose into two glucose units. Write an equation (in words) for the enzymatic conversion of starch to glucose. Classify each of the carbohydrates in the equation as a disaccharide, monosaccharide, or polysaccharide.

Interpretation Introduction

Interpretation:

An equation for the enzymatic conversion of starch to glucose has to be written in words and each of the carbohydrate in the equation has to be classified as disaccharides, monosaccharides or polysaccharides.

Concept introduction:

Polysaccharides are chains of monosaccharides.

Disaccharide composed of two monosaccharides.

Glucose, maltose and starch are monosaccharides, disaccharides and polysaccharides respectively.

Answer to Problem 20.20UKC

The equation for the enzymatic conversion of starch to glucose is,

$\text{starch}\stackrel{\text{α-amylase}}{\to }\text{maltose}\stackrel{\text{maltase}}{\to }\text{glucose}$

Glucose is a monosaccharide, maltose is a disaccharide and starch is a polysaccharide.

Explanation of Solution

The carbohydrates in the potatoes are in starch form, starch is polysaccharide so it hydrolyzed to its simple forms by enzyme catalysis.

The enzymatic conversion of starch into maltose then into glucose is done by enzyme $\text{α-amylase}$ and maltase respectively.

Hence,

The equation for the enzymatic conversion of starch to glucose is,

$\text{starch}\stackrel{\text{α-amylase}}{\to }\text{maltose}\stackrel{\text{maltase}}{\to }\text{glucose}$

Here the glucose is a monosaccharide, maltose is a disaccharide and starch is a polysaccharide.