These are most plentiful in the plant's secondary root system, its tubers.
这些都是最丰富的植物的根系中学，其块茎。
Describe the difference of secondary structure between root and stem.
简述根与茎次生结构的区别？
The secondary structure of root has large vessel diameter.
根的次生木质部导管大。
The secondary structure of root has large vessel diameter.
根的次生木质部导管大。
应用推荐