What is Starch
Chemically, all starch a string of glucose molecules bound together. Starch is a polysaccharide, and the main ingredient used by plants to store glucose which can then be converted into energy.
One of the ways in which plants store starch in grains, another is in the specialized agencies. Some examples of starch sources are beans, corn, wheat and potatoes. When people consume starch, breaks an enzyme in the body bonds between glucose molecules, allowing glucose to be absorbed easily into the bloodstream. The human body then sends the glucose or sugar to what parts of the body need energy or store it. The sugar is stored as a special polymer called glycogen which can be used for energy when needed.
What is Cellulose
As starch, cellulose is one polysaccharide. Despite this, divides cellulose chemical starch in that instead of there being a chain of glucose molecules, it is a two-dimensional structure with glucose and hydrogen units linked by polymers. This makes the cellulose more stable. Cellulose, which is exactly the cellulose fiber, can not be digested by humans at all. Instead simply passes through the body via the digestive tract and is not absorbed as starch.
Use of Cellulose of humans, animals and plants
Although it can not be absorbed by the human body, cellulose remains an important part of the human diet because it keeps the digestive system healthy by giving it a workout.
In plants cellulose is a building block that is used to provide support to various parts like the leaves and stem.
Some animals and insects such as cows and termites can absorb cellulose because they have bacteria in the gut papers that actually digest it for them.