physical change decomposer structures
cycle contract potential energy consumer
producer renewable solution mixture
endangered environment investigation
magnetic food chain renewable resource
conservation solution vibrations
evaporation rock ecosystem expand
extinct metamorphosis amphibians
kinetic energy herbivore erosion
mammals weathering condensation
axis environment investigate system
pollination solar system experiment
dispersal vertebrate adaptation water
population experiment germinate
magnetism nonrenewable resource balance
equator revolution invertebrate
rotation traits carnivore mixture
community migrate reptiles sound