中医针灸医师证考试:¡¡translate!!

来源:百度文库 编辑:高校问答 时间:2024/07/06 19:52:12
The producers vary greatly in size, but a single grass, plant or alga,for example ,is given the same status as a single tree.This explains why is a true pyramid shape is often not obtained. Also parasitic food chains may give inverted pyramid of numbers.