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