Third, magnetism in rocks can be used to estimate the age of a fossil site. This method uses the orientation of the Earth's magnetic field, which has changed through time, to determine ages for fossils and rocks.
Some animals, particularly ruminants and termites, can digest cellulose with the help of symbiotic micro-organisms that live in their guts, such as Trichonympha. In humans, cellulose acts as a hydrophilic bulking agent for feces and is often referred to as a  dietary fiber .
RELATED ARTICLES. Cellulose is a polysaccharide (a form of carbohydrate) that has a structural role in animals and plants. In plants, cellulose is the compound that gives rigidity to the cells. The bonds between each cellulose molecule are very strong, which makes cellulose very hard to break down. Because there are so many plants in the world (think of all the flowers, trees, weeds, grasses, vines, and bushes), cellulose, which is found in every cell of every plant, is the most abundant organic compound on earth.