Parliament consists of the Queen, represented by the Governor General, the Senate and the House of Representatives. The Governor-General summons Parliament, brings its session to an end by prorogation, and formally assents to every bill before it can become law. In practice, he exercises all these powers on the advice of the Prime Minister and the Cabinet.
The passage of legislation depends on the participation of all three component parts of Parliament. A bill must be agreed to by both Houses and receive the Royal Assent before it can become an Act of Parliament. The powers of the Senate and the House of Representatives are constitutionally equal except that financial legislation may not be introduced in the Senate.
All Senators are appointed by the Governor General on the advice of the Prime Minister and the Leader of the Opposition.
The House of Representatives is directly elected by the people, and although by tradition the Senate is the Upper House and the House of Representatives is the Lower House, it is the House of Representatives which plays the predominant part in the parliamentary system.