Cellulose is a lot stronger than starch. Starch is practically
useless
as a material, but celluose is strong enough to make fibers from, and
hence rope, clothing, etc. Cellulose doesn't dissolve in water the way
starch will, and doesn't break down as easily.
Your body contains
enzymes that break starch down into glucose to fuel your body. But
we humans don't have enzymes that can break down cellulose.
