The part of the US government that carries out laws is the legislative branch, that is in charge of the United States Congress.
The United States Congress is the depository of the legislative power of the United States. It is a bicameral body, composed of the House of Representatives and the Senate.
The House of Representatives has 435 members representing a congressional district they serve for a biennium. The positions are divided according to the population of each state. Currently, its number does not grow, although in the beginning, one representative corresponded to every 30,000 people.
In contrast, each state has two Senators, regardless of their population. There are 100 senators, who serve at least six years. Both the representatives and the senators are elected by the people.