Chapter 18, Problem 18.149EP

(a)

Interpretation Introduction

Interpretation: The difference between amylopectin of starch and glycogen in terms of the given property has to be stated.

Concept introduction: Amylopectin is a polysaccharide component of starch.  It is a branched glucose polymer.  It accounts about $80\text{\%}-85\text{\%}$ of the starch.  There are about 100,000 units of glucose present in amylopectin.  Glycogen is a storage monosaccharide. It stores glucose in human body and animals.

Answer to Problem 18.149EP

The type of glycosidic linkage present in amylopectin and glycogen is same, that is both have $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ linkages.

Explanation of Solution

Amylopectin is a branched polysaccharide of starch.  Only one type of monosaccharide, glucose is present in amylopectin.  The glycosidic linkages present in amylopectin are $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ linkage between the glucose units.

Glycogen is a branched glucose polysaccharide.  In humans and animals, it stores glucose.  When excess of glucose is present in the human body, it is stored as glycogen.  In glycogen, both $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ glycosidic linkages are present.

Hence, the type of glycosidic linkage present in amylopectin and glycogen is same, that is both have $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ linkages.

(b)

Interpretation Introduction

Interpretation: The difference between amylopectin of starch and glycogen in terms of the given property has to be stated.

Concept introduction: Amylopectin is a polysaccharide component of starch.  It is a branched glucose polymer.  It accounts about $80\text{\%}-85\text{\%}$ of the starch.  There are about 100,000 units of glucose present in amylopectin.  Glycogen is a storage monosaccharide.  It stores glucose in human body and animals.

Answer to Problem 18.149EP

The type of monosaccharide monomer units present in amylopectin and glycogen is same, that is both have glucose as its monomer units.

Explanation of Solution

Amylopectin is a branched polysaccharide of starch.  Only one type of monosaccharide, glucose is present in amylopectin.  The glycosidic linkages present in amylopectin are $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ linkage between the glucose units.

Glycogen is a branched glucose polysaccharide.  In humans and animals, it stores glucose.  When excess of glucose is present in the human body, it is stored as glycogen.  In glycogen, both $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ glycosidic linkages are present.

Hence, the type of monosaccharide monomer units present in amylopectin and glycogen is same, that is both have glucose as its monomer units.

(c)

Interpretation Introduction

Interpretation: The difference between amylopectin of starch and glycogen in terms of the given property has to be stated.

Concept introduction: Amylopectin is a polysaccharide component of starch.  It is a branched glucose polymer.  It accounts about $80\text{\%}-85\text{\%}$ of the starch.  There are about 100,000 units of glucose present in amylopectin.  Glycogen is a storage monosaccharide.  It stores glucose in human body and animals.

Answer to Problem 18.149EP

The degree of branching is more in glycogen than amylopectin.

Explanation of Solution

Amylopectin is a branched polysaccharide of starch.  Only one type of monosaccharide, glucose is present in amylopectin.  The glycosidic linkages present in amylopectin are $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ linkage between the glucose units.

Glycogen is a branched glucose polysaccharide.  In humans and animals, it stores glucose.  When excess of glucose is present in the human body, it is stored as glycogen.  In glycogen, both $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ glycosidic linkages are present.

The difference between amylopectin and glycogen is based on the presence of glucose units in between the branches and the total number of glucose units present in the carbohydrate.  There is about three times more branching in glycogen than amylopectin.  There are about 1000,000 units of glucose present in glycogen while in amylopectin 10,000 units of glucose are present.

Hence, the degree of branching is more in glycogen than amylopectin.

(d)

Interpretation Introduction

Interpretation: The difference between amylopectin of starch and glycogen in terms of the given property has to be stated.

Concept introduction: Amylopectin is a polysaccharide component of starch. It is a branched glucose polymer.  It accounts about $80\text{\%}-85\text{\%}$ of the starch.  There are about 100,000 units of glucose present in amylopectin.  Glycogen is a storage monosaccharide.  It stores glucose in human body and animals.

Answer to Problem 18.149EP

The more number of units are present in glycogen than amylopectin.

Explanation of Solution

Amylopectin is a branched polysaccharide of starch.  Only one type of monosaccharide, glucose is present in amylopectin.  The glycosidic linkages present in amylopectin are $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ linkage between the glucose units.

Glycogen is a branched glucose polysaccharide.  In humans and animals, it stores glucose.  When excess of glucose is present in the human body, it is stored as glycogen.  In glycogen, both $\alpha \left(\text{1}\to \text{4}\right)$ and $\alpha \left(\text{1}\to 6\right)$ glycosidic linkages are present.

The difference between amylopectin and glycogen is based on the presence of glucose units in between the branches and the total number of glucose units present in the carbohydrate.  There is about three times more branching in glycogen than amylopectin.  There are about 1000,000 units of glucose present in glycogen while in amylopectin 10,000 units of glucose are present.

Hence, more number of units are present in glycogen than amylopectin.