The Congreso de la Unión is the legislative branch of the Mexican government, consisting of two chambers: the Senate and the Chamber of Deputies. It is responsible for making laws, approving the budget, and overseeing the executive branch. The Congress meets in Mexico City and plays a crucial role in the country's democratic process. Members of the Senate serve six-year terms, while deputies serve three-year terms. The Congress also has the power to ratify treaties and approve constitutional amendments. Its functions are essential for maintaining checks and balances within the Mexican political system.