Five related questions regarding the relics which consecrate Roman Catholic altars?

The altars in Roman Catholic churches must be consecrated with a saint's relic (preferably a martyred saint). These "relics" are body parts, usually a small bone fragment but sometimes what is referred to as a "major" relic is incorporated within or under the altar. A major relic could be an arm, a leg, or perhaps even an entire body. I have five questions pertaining to this method of consecration: 1) Are altars with major relics more consecrated than others? If not, why use a whole leg? 2) Does the relic play a role in transubstantiation ? 3) Is there a stockpile or inventory of body parts kept somewhere awaiting the consecration of new altars? 4) In the event that a Roman Catholic church closes, is the relic recovered? Is it "retired" or returned to "inventory"? 5) Is there a searchable database listing which relics are associated with each Church? Can we know how large a piece of saint is used or merely the saint's name?