Definition: 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.
Definition: position of an organism in a food web. May be described verbally with descriptors including primary producer, herbivore or carnivore. If described numerically, 1 indicates a primary producer, 2 a herbivore, and so on up the food web.