An apparatus has a valve body defining a first passageway, a valve seat, and a flow aperture extending through the valve body and coupled in fluid communication with the first passageway. An elastic valve cover includes a valve portion overlying the valve seat, forming an interference fit with the valve seat, and defining an axially-extending valve opening therebetween. The valve portion is movable between a normally closed position with the valve portion engaging the valve seat, and an open position with at least a segment of the valve portion spaced away from the valve seat to allow the passage of fluid from the flow aperture through the valve opening. A hermetically sealed variable-volume storage chamber is connectible in fluid communication with the one-way valve assembly. A pump is coupled between the variable-volume storage chamber and the one-way valve assembly to dispense discrete portions of fluid through the valve assembly.