Définition : A liquid tissue; its major function is to transport oxygen throughout the body. It also supplies the tissues with nutrients, removes waste products, and contains various components of the immune system defending the body against infection.
Définition : A grassland biome is a terrestrial biome which includes, across its entire spatial extent, an unbroken layer of grasses (Gramineae), sedges (Cyperaceae) or rushes (Juncaceae).
Définition : A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)
