sec 5 par 1. The House of Representatives shall be composed of not more than two hundred and fifty members, unless otherwise fixed by law, who shall be elected from legislative districts apportioned among the provinces, cities, and the Metropolitan Manila area in accordance with the number of their respective inhabitants, and on the basis of a uniform and progressive ratio, and those who, as provided by law, shall be elected through a party-list system of registered national, regional, and sectoral parties or organizations.