Civil Engineering Reference
In-Depth Information
11
Materials of animal origin
Animals are mainly herbivores. Certain species, such as cows, can digest carbo-
hydrate cellulose and change it into food. Man is mainly dependent on an intake
of carbohydrates in the form of sugar and starch, but also needs protein, carbo-
hydrate, vitamins, minerals, etc.
Humans and animals depend entirely on air for respiration. Oxygen enriches
the blood and makes the body capable of burning food in an exothermic reaction
releasing heat, approximately 80-150 W for an adult, depending upon their
activity.
Figure 11.1: The woollen fibres of a sheep can be used as the main ingredients in paper, sealing
strips and insulation. The bones, milk and blood can form the basis of materials for binders for
glue and paint.
