The main system of our body r skeletal system,muscular system,nervous system ,digestive system,circulatory system,respiratory system and excretory system . Everything that we do is depended on these systems.Our muscular system helps us to move our teeth with the help of jaw bones.Muscles cannot push so we need  at least  2 muscles at a joint. while one contracts the other relaxes thus helping them  move.As we chew our food it goes into the food pipe to the stomach.The stomach releases acids and  digest .the liver and pancreas break them  more .the small intestine acts like a filter which  separates the nutrients from waste matter .It then goes into the large intestine which acts like a  pipe to  the anus which releases waste 
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