The human body is very complex. It's like a job. You have to do a million things in a day to get through the day. The body uses nine systems to do all of these jobs. They all have separate functions, but some work together. Every system is also made up of organs. There are many ways to care for and protect systems from the many different problems they can have. There are also many interesting facts about each system. The main function of the nervous system is to coordinate all the activities of the body. The main organs are the cerebellum, which controls and coordinates movement. The brain is the center of conscious thought, learning and memory. The last major organ is the brainstem. The brainstem keeps the body's automatic systems functioning. Nervous system problems include epilepsy, Alzheimer's disease, and multiple sclerosis. You can take care of your nervous system by wearing a seat belt, wearing a helmet, and not using drugs or alcohol. Something very confusing about the nervous system is that the left side of the human brain controls the right side of the body and the right side of the brain controls the left side of the body! The skin has 3 main functions. It must regulate body temperature, eliminate waste (sweat) and protect. The skin is made up of 3 layers. The epidermis is the thinnest outer layer of the skin made up of dead and living cells. The dermis is the thickest middle layer of the skin that contains blood vessels and nerves. Sweat glands are located in the dermis and secrete sweat through ducts to pores on the surface of the skin. To avoid problems such as warts, pimples, moles, acne and sunburn you can wash your body every day, wear a sunscreen of 15 or higher and check your body often... middle of the paper... culatory system. The pituitary gland is a growth hormone that helps in mertabolism and develops the reproductive organs. The thyroid controls metabolism based on how quickly the body breaks down food. The adrenal gland secretes many hormones including adrenaline which prepares the body to react in a stressful situation. The pancreas produces digestive enzymes and insulin. The ovaries produce eggs and estrogen. The testes produce sperm and testosterone. To stay healthy you should undergo regular medical check-ups, eat a balanced diet, sleep at least 8 hours and reduce stress in your life. Some problems are growth disorders, diabetes and obesity. Puberty begins at different times for girls than boys. Girls start at around 9-13 years old and boys at 10-15 years old. The body is an extraordinary thing. There are so many things happening at once. Without your eyes you would not be able to see this paper!