A microsystem for fluidic applications includes a substrate with a reservoir, a first microchannel, connected to the reservoir, and a second microchannel, separated from the first microchannel by a fixed member. The microsystem furthermore has an elastic film on the substrate, which film has a joint to the substrate around the reservoir and seals the reservoir. Here, the joint has a permanent joining area and, on the fixed member, a fixed member joining area that can be broken open and adjoins the permanent joining area at both ends of the fixed member. Such a microsystem forms a processing chip with reagent receptacle.