The Virginia Plan, written by James Madison, had ideas of a bicameral legislature. They also thought that representation by state should be determined by the population that a state has.
James Madison was a smart dude, so he also wrote that the government should be split into three parts, a legislative branch, an executive branch, and a judicial branch.
Therefore, the elements in the Virginia Plan that became part of the government were : bicameral legislatur judicial branch executive branch.