Flowers and animals; we can't live without them. The flora of the earth produce the oxygen that is breathed by the fauna and in turn, the fauna exhale the carbon dioxide that the flora need to live. One cannot live without the other, and humans cannot live without either; hence their importance.
Flora and fauna are the plant and animal life of a region in a period of time. That may sound simple, but the ecosystem created by the interdependence of these two life forms is not simple at all. In fact, humans cannot breathe unless both flora and fauna survive and thrive on the earth.
The very air we breathe and the food we eat, the medicines that cure us, and the water that keeps us alive would not exist were it not for flora and fauna. All things in an ecosystem are interdependent. The existence of one species may depend on the health of another, such as the relationship of bamboo forests to pandas. Pandas only eat bamboo shoots, so the destruction of the bamboo forests in China resulted in the endangerment of the Panda, due to starvation and loss of habitat.
In China, destruction of the forests left the tigers with no place to go. Farmers killed them in great numbers to protect their farm animals, and soon there were few left. In an attempt to save the species, Chinese tigers were moved to the forests of Africa, where they are surviving nicely.