3. The digestive system The main organs of the digestive system are the tongue, the esophagus, the stomach and the small and large intestine. The main function is to digest food and get rid of waste. More info:http://www.innerbody.com/image/digeov.htmlhttp://www.innerbody.com/image/digeov.html

4. The Circulatory System The circulatory system is made up of several parts. The main organ is the heart. Other parts of this system are the blood vessels which are the arteries, the veins and the capillaries The main function is to pump the blood throughout the body, which carries the oxygen to the cells and the carbon dioxide back to the lungs. More info:http://www.innerbody.com/image/cardov.htmlhttp://www.innerbody.com/image/cardov.html

5. The Respiratory System The main organs in the respiratory system are the nasal cavity (nose) trachea, lungs, bronchi, and diaphragm. The purpose of this system is to take in oxygen from the air you breathe and to release carbon dioxide back into the air. As the blood passes through the lungs, it picks up the oxygen and takes it to the cells of the body, where the blood then picks up carbon dioxide and returns it to the lungs. More info: http://www.innerbody.com/image/cardov.htmlhttp://www.innerbody.com/image/cardov.html

6. The Skeletal System The main organs of the skeletal system are the bones. There are 206 bones in the human body.. The main function of the skeletal system is to give your body its shape and provide support. The bones also protect your internal organs. More info:http://www.innerbody.com/ skelfov.html image/http://www.innerbody.com/ skelfov.html image/

7. The Muscular System Each of more than 600 muscles is served by nerves which link the muscle to the brain and spinal cord. Our bodily needs demand that muscles accomplish different chores, so we are equipped with three types of muscle: cardiac, smooth and skeletal. The main organs in the muscular system are the muscles. More Info:http://www.innerbody.com/htm/body.htmlhttp://www.innerbody.com/htm/body.html

8. The Nervous System The main purpose of the nervous system is to help you control your body and to respond to to your environment. The main organs of the nervous system are the brain, spinal cord and nerves. More Info: http://www.innerbody.com/htm/body/html

9. The Endocrine System The main purpose of the endocrine system is to help control body functions and regulate growth and develop- ment. The main organs in this system are called glands. These glands produce chemicals called hormones. These hormones are what regulates the growth and development of the body. The main glands are the hypothalamus, pituitary, thyroid, parathyroid, thymus, pancreas and the. adrenal glands More info: http://www.innerbody.com/htm/body.html

10. The Integumentary System The skin, hair,and nails are the main organs of the integumentary system and the main function is to provide the body with a protective layer and covering. The skin is made up of three layers: the top layer is the epidermis, the middle layer is the dermis and the bottom or underneath layer is the fatty layer. The hair follicles grow from the fatty layer through the dermis and exit the skin through pores in the epidermis.

11. The Excretory System The function of the excretory system is to remove waste from your body. This can be remembered by the word exit or excrete. The waste products of the body exit the body through the excretory system. The main organs of this system are the kidneys, urinary bladder, and the urethra. More info: http://www.innerbody.com/htm/body.html

12. The Reproductive System The reproductive system is composed of the male and female organs. The main function of this system is to allow the human body to reproduce offsprings for the human race. As in all living organisms, reproduction is necessary for the continuance of life. More info: http://www.innerbody.com/htm/body.html