Question: are all the states made up of two houses

Answer: No, Every state except Nebraska has a bicameral legislature, meaning that the legislature consists of two separate legislative chambers or houses. In each case the smaller chamber is called the Senate and is usually referred to as the upper house. This chamber typically, but not always, has the exclusive power to confirm appointments made by the governor and to try articles of impeachment. (In a few states, a separate Executive Council, composed of members elected from large districts, performs the confirmation function.) Members of the smaller chamber represent more citizens and usually serve for longer terms than members of the larger chamber, generally four years. In 41 states, the larger chamber is called the House of Representatives. Five states designate the larger chamber the Assembly and three states call it the House of Delegates. Members of the larger chamber usually serve for terms of two years. The larger chamber customarily has the exclusive power to initiate taxing legislation and articles of impeachment.