Scelta multipla
The polysaccharide that you are most likely to have eaten recently is __________.
2611
views
2. Cell Chemistry & Cell Components
Carbohydrates
Scelta multipla
Amylase is an enzyme that breaks down starch. Why can the same enzyme not break down cellulose?
A
The enzyme cannot attack cellulose because of its helical shape.
B
Cellulose molecules are much too large.
C
Starch is made of glucose; cellulose is made of fructose.
D
The bonds between the monosaccharide monomers in cellulose are much stronger.
E
The monosaccharide monomers in cellulose are bonded together differently than those in starch.
Guida verificata passo dopo passo1
Understand the role of amylase: Amylase is an enzyme that catalyzes the hydrolysis of starch into sugars. It specifically targets the glycosidic bonds in starch molecules.
Identify the structure of starch: Starch is composed of glucose monomers linked by α(1→4) glycosidic bonds, which form a helical structure that amylase can easily access and break down.
Examine the structure of cellulose: Cellulose is also composed of glucose monomers, but they are linked by β(1→4) glycosidic bonds, resulting in a linear, fibrous structure that is not accessible to amylase.
Recognize the specificity of enzymes: Enzymes like amylase are highly specific to the type of bond they can break. Amylase is designed to interact with α(1→4) bonds, not β(1→4) bonds.
Conclude why amylase cannot break down cellulose: The difference in glycosidic bond types between starch and cellulose means that amylase cannot interact with or break the β(1→4) bonds in cellulose, thus preventing its breakdown.
Video correlati
Pratica correlata
