The main function of the human digestive system is to take in food and absorb the nutrients from the food and transport them to the places it needs to be


The main function of the human digestive system is to take in food and absorb the nutrients from the food and transport them to the places it needs to be, the mouth, pharynx, oesophagus, stomach, pancreas, liver, gall bladder and the small and large intestine are all part of the system. The main function of the cardiovascular system is to transport gases, nutrients and other waste products all around the body also the cardiovascular system is responsible for protecting the body from any infections and to help control the body temperature. Furthermore, another function of the cardiovascular system is to help maintain body fluid. The main organs within the cardiovascular system is the heart and blood vessels which is things such as arteries, capillaries, veins and blood. The function of the respiratory system is to take in oxygen and expel carbon dioxide.
The digestive, cardiovascular and respiratory system are connected because when we eat the food travels from our mouth down where it is broken down by us chewing, down the pharynx and oesophagus to the stomach. When the food and liquids have reached the stomach, the stomach produces enzymes which break down the food even more so that it can be passed on to the small intestine where the nutrients are get into the blood. When the food reaches the small intestine it gets into the blood through villus, the main function of villi is to absorb nutrients from the food eaten by the host they, the average size of one villi is 0.5 – 1.6mm. The reason why food nutrients can diffuse from the small intestine into the blood stream is because the blood supply to the villi has a low concentration of food allowing diffusion to occur. The digestive, cardiovascular and respiratory system are connected because when the nutrients get into the blood stream it will be transported all around the body, with the oxygen that is breathed in and diffused from our lungs into the blood stream. The nutrients and oxygen travel all around the body to cells that require them, all cells require oxygen in order to survive, furthermore all cells require glucose in order to survive. Furthermore, cells require protein because they control the function and structure of the tissues and organs within the body.
The digestive, cardiovascular and respiratory system are connected because of respiration, Respiration is when we release energy from glucose within the muscles, and the word equation for this is: Glucose + oxygen ? energy + water + carbon dioxide. There are two types of respiration, aerobic respiration and anaerobic respiration, aerobic respiration requires oxygen and anaerobic respiration does not require oxygen. Aerobic respiration produces carbon dioxide and water as a waste product by using up oxygen and glucose, furthermore aerobic respiration in mitochondria cells and is controlled by enzymes. Anaerobic respiration normally happens during exercise; this type of respiration does not require oxygen. When we breathe in oxygen enters our lungs and diffuses into our blood where it is transported along the circulatory system along with the nutrients in the blood stream. The waste products in our body is carbon dioxide and urea, carbon dioxide is produced because of aerobic respiration, it is removed from our lungs when we breathe out. The carbon dioxide come from the cardiovascular system as it is a waste product of respiration, it is then diffused from the blood stream to the lungs and exits our body through our mouth, this is how the respiratory system and circulatory system are connected. Urea is also a waste product and it is produced when to many amino acids are broke down, the kidneys are responsible for removing urea and it does this by making urine, this is stored in the bladder. The digestive system and circulatory system are connected because when nutrients are absorbed from food they travel down to the small intestine where they are then absorbed into the circulatory system. For example, vitamins and minerals are absorbed into the blood stream from the small intestine it then travels with the blood stream all around the body until it gets to the liver and then kidney and then it is sent out through urine.
The respiratory system and cardiovascular system are linked because when exercising the cardiovascular system works harder, your heart rate is expected to increase, which means there will be an increase in stroke volume, your muscles, will demand more oxygen. Furthermore, the cardiovascular system will produce more waste and there will be an increase in temperature. This is because the body will require more oxygen when exercising because as muscles need to produce more energy, furthermore, when exercising the respiratory system is also affected as you will have to take in more oxygen. When exercising the body’s muscles are in high demand of oxygen meaning that the respiratory system will have to take in more oxygen, the oxygen will then be diffused into the blood stream from the lungs and then transported to the muscles that require, this is how the cardiovascular system and respiratory system are linked.