Of course there are specialists which are restricted to a narrow range of foods including animals which are:
feeding upon dung
feeding on blood
feeding on wood
eating or living on honey
living or feeding on eggs
feeding on decaying substances
feeding on seeds
feeding on worms
Animals have evolved a number of feeding mechanisms to catch and ingest their repasts including:
Feeding Mechanisms Examples suspension feeders clams and other bivalves substrate feeders Mediterranean Fruit Fly fluid feeders mosquito, vampire bat bulk feeders most animals
Animals process food in four stages which are:
Of these four we will concentrate on the digestion and absorption of food.
Where does digestion take place?
- Within food vacuoles inside a cell obtained by endocytosis. This is intracellular digestion and occurs in protozoans and white blood cells.
- Within gastrovascular cavities or in alimentary canals. Animals ingest their food, but it remains outside the body proper. This is extracellular digestion.
- gastrovascular cavities require the same opening for ingestion and elimination. Once inside the cavity, food is both digested and transported to areas that need nourishment.
- alimentary canals are continuous passages from mouth to anus. Food is moved from chamber to chamber by smooth muscle contractions called peristalsis.
Compartments within the alimentary canal include:
- Oral cavity
- Small Intestine
- Large Intestine