根和根冠被一鞘 状 结构,即胚根鞘所覆盖.Both root and root cap are covered by a sheath - like structure called the coleorhiza.用来保护发育的胚芽的鞘状的结构.Coleoptile A sheath like structure that protects the developing plumule in grasses.胚根鞘:保护幼根的鞘状结构....