Circulatory System: Facts, Function & Diseases. The circulatory system is a vast network of organs and vessels that is responsible for the flow of blood, nutrients, hormones, oxygen and other gases to and from cells.
And I must make one more important point about all this maximum benefit business. I just said that the maximum Social Security benefit this year is $2,663. But there are many people getting more than that.
In June 2011, the average Social Security benefit was  $1,180.80 per month. The maximum possible benefit for a worker retiring at age 66 in 2011 is $2,366. But to get this amount, the worker would need to earn the maximum taxable amount, currently $106,800, each year after age 21.