My two chosen systems I will be writing about is the cardiovascular system and Digestive system.
(P4) the digestion system
The digestive system is also known as the alimentary canal from the mouth to the anus.
Digestion is a process in which insoluble food is broken down into particles which are made into soluble particles enough to be absorbed and to be used by the body and into the bloodstream. These soluble particles are major macronutrients made up of protein, carbohydrates and fats which are needed for essential maintenance for the functioning of the human body. Nutrients are found in foods- proteins are found in red meat/poultry; sources of carbohydrates include rice and wheat. Fats are found in dairy products.
Carbohydrates are the main source of energy for the body; carbohydrates can be sugars, (monosaccharaides e.g. glucose) or starch. (Polysaccharides). Proteins are needed for repair, growth and repairing of the body. Fats are important for the absorption of vitamins and also in the forming of and insulating lair to keep the body warm.
Mechanical digestion happens in the mouth with the movements of the jaws and teeth and within the stomach and the intestine this is by the churning action of the muscular walls. Chemical digestion is by a series of specific enzymes in which are produced within numerous regions of the alimentary canal. The salivary glands produce an enzyme called amylase which breaks down polysaccharides into simpler sugars. These enzymes then hydrolyse the chemicals within the larger food molecules by breaking them down into very tiny constituent molecules.
In the mouth the larger particles of food are broken down physically by mastication and mixed with the saliva by the movement of the tongue. There are four types of teeth each teeth has a different shape and a different function these are;
* Incisors = these are at the front of the mouth and have