Why is the rain forest important for life on Earth?

Answer 1

Plants remove Carbon Dioxide [one of the major "Greenhouse" gasses] from the atmosphere, and release oxygen into the air so a large rainforest will continually refresh the atmosphere.

Rainforests also provide homes to many amazing species of plants and animals, some of which are not found anywhere else on the planet. If that's not a good enough reason to save the rainforests, I don't know what is! And also to save the gorillas.