The most important part of the Holy Mass is the consecration where the bread and wine become the Body and Blood of Christ. This is also where the faithful genuflect because this where we see our Lord Jesus Christ in the form of the bread and wine. But, how can be a bread and wine become the Body and Blood of our Lord? The taste of the host does not change when we receive it from the priest (though its taste is very different from most bread). The change by which the bread and wine in the Eucharist becomes Christ's real presence—that is, his body and blood, is called Transubstantiation.