Which are plant tissues that form the plant roots?
Roots have a central portion called medulla made of vascular tissue outer phloem and inner xylem. Medulla is delimited by pericycle and surrounded by the medullary parenchyma, a meristem that originates the secondary roots (ramifications). Externally to medulla lies the cortical portion formed of endodermis that surrounds the pericycle and cortical parenchyma. The covering of roots is epidermis with root hairs later substituted by suberized (corky) periderm.