This essay aims to explain the structure and functions of the digestion system, starting from consuming a cooked dinner to chemical and physical changes within the body, to prepare or help absorption of vital nutrients and help disposal of waste.
The structure of the digestive system starts with the gastrointestinal tract, it is a tube that runs from the mouth to the anus and because of this some scientist says it is an external organ; there are also accessory organs for digestion, the salivary glands, teeth, tongue, liver, gall bladder and pancreas. The function of the digestive system is to breakdown food, so nutrients can enter the blood and lymph system.
To start this process, we have to start with the mouth, when food is put in to the mouth you start the process of digestion, the structure of the mouth is made up of the lips, teeth, tongue, salivary glands, soft palate and pharynx. The lips function is to hold food in. The salivary glands, there are three sets of salivary glands, the parotid glands which are in front of the ears one on each side of the face, then the submandibular glands that are below the jaw and the sublingual glands, that are either side the tongue, under the floor of the mouth all these start the chemical process within the mouth by making salvia to help moisten and dissolve food, saliva is made up of water, mucus, a bacterial agent and also has a carbohydrase enzyme called salivary amylase which helps convert starch into maltose. An enzyme, lysozyme destroys harmful bacteria, and saliva has a pH of 6.8; salivary also activates taste buds and lubricates the mouth. Teeth play a large part within the mouth by chewing and crushing food into smaller pieces to be swallowed, there are 4 types of teeth and they play all play a part, incisors are for cutting though food, canines are for tearing and shredding, molars and premolars are for crushing and grinding your food. The tongue’s