The enzymes that digest carbohydrates are very specific and can only digest specific glucose monomers of a Polysaccharides. For example our body can digest starch since its made up of α-glucose monomers (the difference of α-glucose and β-glucose is just on the location of the hydroxl group). However <span>Polysaccharides</span> like cellulose are indigestible because cellulose is made up of β-glucose and the enzyme which digests polysaccharides in humans (amylase) cannot detect β-glucose linkages.
Decomposers break down the remains of dead plants and animals and take the nutrients and energy and give it back to the earth when they die.
It was used till the 1960s. Hope i helped.
The contractile vacuole expels excess fluid from the cell.