sentences: food supply often limits predator population size in an ecosystem & a bear is a kind of predator ->  food supply may limit the bear population in an ecosystem  food supply may limit the bear population in an ecosystem & population is a measure of the number of a species in an environment ->  food supply may limit the number of bears in an ecosystem  food supply may limit the number of bears in an ecosystem & a forest is a kind of ecosystem -> food supply may limit the number of bears in an forest