The legislature of a federal system of government is usually bicameral. This means that it consists of two chambers or houses. This is because the legislature has to provide adequate representation at different levels. It balances the interests of the central government and the constituent states or regions. 

For example, in Nigeria, the National Assembly is bicameral, comprising the Senate (upper house) and the House of Representatives (lower house). This setup is common in federal systems worldwide, such as the United States and Switzerland.