Articles of Confederation: Unicameral Legislature; Constitution: Bicameral Legislature
The structure of Congress during the Articles of Confederation was weak, as the Continental Congress created it like that with the intention of not having a monarchy like Britain’s. The Articles of Confederation had a unicameral legislature, with each state having only one vote, regardless of population.
The Constitution made congress have a bicameral legislature and three branches of government (legislative, judicial, and executive) to ensure that the congress and government wouldn’t have too much power.