<Li> Performance of ceremonial functions . </Li> <P> Regular ceremonies of the Emperor with a constitutional basis are the Imperial Investitures (Shinninshiki) in the Tokyo Imperial Palace and the Speech from the Throne ceremony in the House of Councillors in the National Diet Building . The latter ceremony opens ordinary and extra sessions of the Diet . Ordinary sessions are opened each January and also after new elections to the House of Representatives . Extra sessions usually convene in the autumn and are opened then . </P> <P> Although the Emperor has been a symbol of continuity with the past, the degree of power exercised by the Emperor has varied considerably throughout Japanese history . In the early 7th century, the Emperor had begun to be called the "Son of Heaven" (天子, tenshi, or 天子 様 tenshi - sama). </P> <P> The title of Emperor was borrowed from China, being derived from Chinese characters and was retroactively applied to the legendary Japanese rulers who reigned prior to the 7th--8th centuries AD . </P>

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