The Function of the Body There are 11 principal physical systems
within the human body. Each of these structures has related
functions indigenous to that system. However, organ systems need
to work together to survive. For instance, bones without muscles
would fall down as would muscle without bone. Imagine a pile of
bones trying to move with nothing to attach to. Picture skin
without bones and muscles to cover. Think about food sitting in
the body with no way out. The cooperative relationship between
the systems presents the highest level of organization within
the body. The 11 major organ systems of the body are:
Integumentary — the skin and related structures Skeletal —
bones, cartilages, and joints Muscular — muscle tissue Nervous —
brain, spinal cord, nerves, and sense organs Endocrine — all the
glands that produce hormones Respiratory — lungs and all air
passageways Cardiovascular — blood, heart, and blood vessels
Immune — lymph, lymph vessels, and lymph structures Digestive —
teeth, esophagus, stomach,