STRUCTURE OF DICOT ROOT:
1.EPIDERMIS: Single layered parenchymatous cells form epidermis with root hairs.
2.CORTEX: Simple multilayered formed with parenchymatous cells with intercellular spaces.
3.EDODERMIS:Single layered, cells possess casparian strips on radial and tangential walls.
4.PERICYCLE : Single layered consisting of thin walled cells.
5.Vascular bundle are radial that means the xylem and phloem strands are arranged on alternate radii separated by parenchymatous cells.Xylem is exarch that means protoxylem towards periphery and metaxylem towards centre.
6.Pith is small and parenchymatous.
MONOCOT ROOT
EPIDERMIS: Single layered with root hairs parenchymatous also called epiblema.
CORTEX: Multilayered parenchymatous in old roots the outer most layer of cortex next to epidermis shows deposition of suberin and act as protective layer called exodermis.
ENDODERMIS: Single layered, cells possess casparian strips on radial and tangential walls.
PERICYCLE : Single layered consisting of thin walled cells.
Vascular bundles radial polyarch ( large no.) and exarch ( protoxylem towards periphery with smaller tracheids & metaxylem towards centre consisting large tracheids).
Pith is large with intercellular spaces and some cells contain starch grain.
•RADIAL: Xylem and phloem are alternate with each other separated by parenchymatous cells.
•,,: Xylem and phloem in the same radius.
•COLLATERAL: Phloem lies towards outerside and xylem towards innerside.
•BICOLLATERAL : Phloem lie on outer and inner side and xylem sandwitch between them.
•CONCENTRIC: One tissue surrounds the other it is of two types:
•AMPHIVASAL : Phloem lies in the centre xylem surrounds it.
•AMPHICRIBAL: Xylem lies in the centre phloem surrounds it.
•EXARCH: Protoxylem towards periphery metaxylem towards centre.
•ENDARCH: Metaxylem towards periphery protoxylem towards centre.
•MESARCH: Protoxylem remain surrounded by metaxylem.
