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Multiple Choice
Amylase is an enzyme that breaks down starch. Why can't the same enzyme break down cellulose?
A
Cellulose has a different glycosidic linkage than starch.
B
Amylase is inhibited by the presence of cellulose.
C
Cellulose is a protein, not a carbohydrate.
D
Cellulose is composed of different monosaccharides than starch.
Verified step by step guidance
1
Understand the structure of starch: Starch is composed of glucose units linked by α(1→4) glycosidic bonds, which are easily broken down by the enzyme amylase.
Understand the structure of cellulose: Cellulose is also composed of glucose units, but they are linked by β(1→4) glycosidic bonds, which have a different spatial configuration.
Recognize the specificity of enzymes: Enzymes like amylase are highly specific to the type of bond they can break. Amylase is specific to α(1→4) glycosidic bonds and cannot act on β(1→4) bonds.
Consider the structural implications: The β(1→4) linkage in cellulose results in a linear, fibrous structure that is not accessible to amylase, unlike the helical structure of starch.
Conclude with the reason: The inability of amylase to break down cellulose is due to the different glycosidic linkage (β instead of α) present in cellulose, not because of inhibition or different monosaccharides.