Nutrition
In the animal kingdom, all organisms are dependent on each other for food and this can be either represented in a food chain which is linear and is only a straight line from start to end or a food web which has many variables or food chains and different routes that could be taken from the producer to the tertiary consumer.
Food Chain
Food Web
Digestive system and Villi
The red fox's digestive system or alimentary canal is the same as all regular mammals. The process all starts out when the food is seen by the fox and the salivary glands in it's mouth begin to produce saliva. Once the food enters the mouth it is then chewed by the teeth and partially dissolved by the saliva. Once it is in small enough pieces it is then swallowed and travels down the esophagus and into the stomach. There is also a part before the esophagus which is called the epiglottis which ensures that no food travels down the trachea which is for breathing. The food is swallowed by the muscles in the esophagus doing an action called the peristaltic movement which is basically closing the space behind the food to push it down. In the stomach, the food mixes with the hydrochloric acid to become a churned up mixture called chyme. From there the duodeum which is the first part of the small intestine. In this section the pancreas supplies insulin to absorb energy and break down the fats as well as the liver releases bile into the chyme which also assists in absorption in the small intestine. As the mixture of bile and chyme travels down the small intestine, the nutrients and fat are absorbed by the specialised cell called villi which are millions of little projections out of the inside surface of the intestine. On these projections are more projections creating the surface area the size of a tennis court in a seven metre tube. The villi work to absorb nutrients straight into the bloodstream including fat which can cause health problems if intake is not controlled and is taken in through the part called the lacteal. Oxygenated and de-oxygenated blood is constantly running through which is what enables the quick absorption. After the small intestine the mixture travels into the large intestine or colon to have the liquid drained out of it. The faeces is then excreted through the rectum and then the anus.
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