The human body system is made up of several different systems with different functions.
The main systems are the skeletal system, muscular system, nervous system, endocrine system, cardiovascular system, lymphatic and immune system, respiratory system, digestive system, urinary system and the reproductive system. Each of these systems work together in harmony.
Each organ and structure in the body fits together to make a complex functioning whole. No other system is so complex or as advanced.
The human body starts to develop these systems from the moment we are conceived at the fetal development stage. Our quickest growth period happens before we are born and by the time we enter the world all of these systems are perfectly formed.
There is growth and development still to occur to aid our bodies defense systems but our life functions are already perfect.