An ecosystem can be as large as the Sahara Desert, ___1___
as small as a puddle. An ecosystem is a dynamic interaction ___2___
plants, animals, and microorganisms and ___3___
environment working together as a functional unit. Ecosystems
will fail ___4___ they do
not remain in balance. No community can carry more organisms
than its food, water and shelter can accommodate. Food and
territory are often balanced by natural phenomena such as fire,
disease, and the number of predators. ___5___
has its own role to play.
Humans have ___6___
the ecosystems in almost every way imaginable ! Every time we
walk out in the wilderness or bulldoze land for a new parking
lot, we are drastically altering an ecosystem. We ___7___
the food chain, the carbon cycle, the nitrogen cycle and the
water cycle. Mining minerals also takes its toll on the
ecosystems. We need to do our best to not interfere in these
ecosystems. |