It pumps blood through the circulatory system to all parts of the body. The blood carries food and oxygen to the cells and carries away carbon dioxide and waste materials.

The right hand side of the heart receives de-oxygenated blood from the body tissues, and pumps it to the lungs. The left-hand side of the heart receives oxygenated blood from the lungs and pumps it into the body, so that the oxygen can be delivered to cells. Respiratory system One of the most important functions of the respiratory system is to supply oxygen to all the cells in the body. Every cell in the body requires a constant supply of oxygen to stay alive.Because most of the cells are not in contact with air, the respiratory system must supply them with oxygen.

Another function is to remove carbon dioxide and water from the body. A lung is associated with respiratory system, the function of the lungs is to let out carbon dioxide and bring in oxygen. Digestive system The primary function of the digestive system is to break down the food we eat into smaller parts so the body can use them to build and nourish cells and provide energy. It also removes undigested waste at intervals. The liver is the main producer of important chemicals.

Stomach is associated with digestive system; the stomach's main function is digestion. It does this by: Storing the food we eat Breaking down the food into a liquidly mixture Mixing enzymes which is are chemicals that break down food Slowly empties that liquidly mixture into the small intestine Renal system The main function of the renal system is to get rid of waste that is found in the urine. The amino acids that are not immediately required are broken down in the liver to make urea; this urea is carried in the bloodstream to the kidneys for elimination of waste.The functions of the renal system, which are performed by the kidneys, are to regulate and maintain the balance of electrolytes and the pH of the fluid that has been processed.

It assists in the production of new red blood cells and it also involved in the maintenance of blood pressure. Kidneys, ureters and bladder are associated with renal system. The main functions of the kidney in order of importance are: Blood pressure control salt and water balance erythropoietin (a hormone) production vitamin D metabolismThe function of ureters is to enter the urinary bladder at an angle to help prevent any back flow (reflux) of urine back into the ureter. The ureter connects the kidney to the urinary bladder and urine is drained from the kidney and stored in the bladder it’s a passage through which urine passes from kidneys to the urinary bladder. The function of bladder is to hold urine the bladder is a sort of pouch found in the end of the genito-urinarian tract. Its function is to retain the urine of the body until it can be released to the urethra and out of the body.

Nervous systemThe nervous system's main function is to control the operation and movements of the body based on the sensory information it gathers, both internally and externally. The functions include: To maintain your consciousness To help you respond to your senses To help coordinate what you sense and feel To allow learning and memory To control other body systems Brain is associated with nervous and brain the most important organ in your body because it controls everything in your body. It can be seen as super sense or sensory motor. The brain controls the functioning of the body electrical impulses.

Endocrine system The endocrine system serves mainly to maintain the body's internal environment, respond to stress, regulate growth and development and contribute to the reproductive processes. Which means it controls and co-ordinates organs. It also maintains blood glucose, water and salt levels. It also assists in reproduction and growth.

Reproductive system The primary direct function of the male reproductive system is to provide the male gamete or spermatozoa for fertilization of the ovum. Other functions include transmission of sperms to the female.The functions of the female reproductive system include production of ovum eggs, receiving the sperms, and child birth. Which means the function of the reproductive system is to produce new offspring. The continuity of the human species is guaranteed through reproduction.

Ovaries are associated with reproductive system, functions of ovaries are to store ovum (eggs) and release them during the menstrual cycle. They make eggs which go on further to be fertilised to make a baby. To produce eggs, to produce hormones or chemicals that regulate menstruation, etc.The ovaries produce the eggs that are fertilized by the sperm and so the baby is formed. Lymphatic system The lymphatic system helps to maintain fluid balance, defend the body against disease, and absorb liquids from the intestine and transport them to the blood. The lymphatic System collects and returns fluid that leaks from blood vessels.

It absorbs fats and vitamins. Lastly, it defends against invading microorganisms and disease. Musculoskeletal system The musculoskeletal system's main purpose (function) is to protect vital organs such as the brain, heart and lungs. Also, to keep structure and stability within the human body.

It also allows the body to move, examples being walking, standing, bending. This means it gives shape to body. It also produces blood cells and stores calcium and phosphorus. Immune system The function of the immune system is to protect our body from infections and illnesses.

Our immune system works to identify pathogens and tumour cells that could cause disease and to eliminate them from your system. Our body's immune system has an incredibly difficult task in doing this because these pathogens and bad cells are sneaky: they can redesign themselves and adapt to changes our body makes to get rid of them.