case study sweet truth not all carbohydrates are alike

Lesson 3

The case study is attached

Questions

1. In aqueous solutions there are three forms of glucose: the ï¡-form (36%), the ï¢-form (64%) and a trace amount

of the open-chain form. At equilibrium, the alpha and beta cyclic forms are interconverted by way of the openchain

structure. Explain (a) why the cyclic forms exist predominately in solutions, and (b) why the ï¢-form is

more abundant than the ï¡-form.

2. Name the monosaccharides and disaccharides in amylose and cellulose. Compare the structural and

conformation diff erences between amylose and cellulose. A simple iodine test can be used to distinguish the two

polysaccharides. Describe the iodine test and explain the observation.

3. Write the reduction reaction of glucose to form sorbitol. List and explain the side eff ects caused by too much

sorbitol consumption.

4. Blood sugar levels can be detected by test strips, which are coated with glucose oxidase and an indicator. Write

the oxidation reaction of glucose that happens in the testing process.

5. Why are soluble fi bers identifi ed as prebiotics?