20. Carbohydrates

Give the name of one or more polysaccharides that matches each of the following descriptions:

(a) not digestible by humans

Describe the similarities and differences in the following:

a. amylose and cellulose

Which plant-based polysaccharide possesses only a-1,4 glycosidic linkages?

Hydrolysis of both glycosidic bonds in the following trisaccharide A, B, C yields three monosaccharides. 

c. Draw the Fischer projections for the three monosaccharides.

Are one or more of the disaccharides maltose, lactose, cellobiose, and sucrose part of the trisaccharide in Problem 20.23? If so, identify which disaccharide and its location. (Hint: Look for an α-1,4 link, β-1,4 link, or 1,2 link, and then determine if the correct monosaccharides are present.)

Amylose (a form of starch) and cellulose are both polymers of glucose. What is the main structural difference between them? What roles do these two polymers have in nature?

How are amylose and amylopectin similar to each other, and how are they different from each other?

Give the name of one or more polysaccharides that matches each of the following descriptions:

c. contains only α(1→4)-glycosidic bonds

Give the name of one or more polysaccharides that matches each of the following descriptions:

b. contains only ß(1→4)-glycosidic bonds

Give the name of one or more polysaccharides that matches each of the following descriptions:

d. produces maltose during digestion

Melezitose, a carbohydrate secreted by insects, has the following Haworth structure:

a. Is melezitose a mono-, di-, or trisaccharide?

Melezitose, a carbohydrate secreted by insects, has the following Haworth structure:

b. What monosaccharides are present in melezitose?

Melezitose, a carbohydrate secreted by insects, has the following Haworth structure:

c. Is melezitose a reducing sugar?

Give the name of one or more polysaccharides that matches each of the following descriptions:

a. not digestible by humans

Describe the similarities and differences in the following:

a. amylose and amylopectin