An Independent Practice Association, or IPA, is an organization comprised of physicians who maintain their independent practices and also join together as an association. The IPA negotiates with organizations, like HMOs, which will supply both patients and income to physicians.
There are 11 major organ systems in the human body, which include the circulatory, respiratory, digestive, excretory, nervous and endocrine systems. The immune, integumentary, skeletal, muscle and reproductive systems are also part of the human body.
Well, there are only three classes of levers, and if the human body has very few first and second class levers, then by the process of elimination, most of the muscles in our body must work as part of third class lever systems. And that is exactly the case.