Blood glucose is internal, has to be an internal receptor. And it is a cell in the on the panc he said, called a beater cell. It picks up high blood lucos and transduces them into what sort of stimulus? Well, this is a hard one, because it's technically in the same cell. So soon as the glucos goes in, that cell de polarizes due to ionic charge changes. This is now going the control center, that high energized cell,. Now is what is basically going to activate the control centr to do the effect.