In contrast with the serial circuit, if we remove a lamp of the support, the other lamp doesn't fade. As always, the electrons flow from the (+) to the (-) pole. When we remove the lamp of one of the supports, the electrons don't move in that branch of the circuit. However, that doesn't implicate that the circuit is closed because the electrons have an alternative way (other branch).
As well as in the serial circuit, for the parallel circuit type there exists several rules for the quantification of the resistance, potential and current intensity. The potential is the same in the two lamps because we have two independent branches. The inverse of the total resistance is equal to the sum of the inverse of the located resistances in the circuit (lamps). In the particular case of the current intensity, this is equal to the sum of the current intensities that pass in each one of the branches.