How are constitution and bicameral connected?

The United States enshrined in the Constitution and put into practice the methods of formation and methods of work of a bicameral parliament, built both on the representation of the entire population and on the representation of the states.

The sense of dividing the US parliament into two chambers is that the bills initiated and adopted by the lower chamber are subject to mandatory approval by members of the upper one, which more often takes the side advocated by the government.