plankton live in bodies of water & a bay is a kind of body of water ->  some plankton live in bays  some plankton live in bays & a factory dumped mercury into a bay ->  mercury is dumped into a bay with plankton  mercury is dumped into a bay with plankton & microorganisms change mercury in a bay into a form that plankton can use ->  mercury is changed into a form that plankton can use in a bay with plankton  an element is a kind of material & mercury is a kind of element ->  mercury is a kind of material  in the food chain process some types of plankton have the role of producer & producers pass materials they use through the food chain ->  plankton pass materials they use through the food chain  mercury is changed into a form that plankton can use in a bay with plankton & mercury is a kind of material & plankton pass materials they use through the food chain -> mercury is passed through the food chain