5.Even though humans are unable to digest cellulose, it is important in our diet because a. we need the chlorophyll contained in plant cells.
b. it allows the stomach to absorb vitamins.
c. it is needed to synthesize vitamin B.
d. it protects the walls of the intestines from mechanical damage.
e. it adds volume to the wastes in our large intestine and ensures that we eliminate toxic
materials more frequently.