蚯蚓深深地钻进底土.Earthworms burrow deep into the subsoil.进入底土的化学物质会减少，这对土质松软的热带土壤而言尤为重要。Less chemical gets into the sub-soil which is particularly important with the light, tropical soils.土壤中含有效锌转低时, 深层耕翻会使缺锌的底土暴露出来.In a solid ...
A large portion of the cytoskeleton consists of threadlike microfilaments composed mainly of the contractile actin.细胞骨架大部分由微丝组成,微丝主要由可收缩的肌动蛋白组成.Organelles are suspended within it, supported by the filamentous network of ...