Q. Fill in the blanks:
a. In (1)______, the protoxylem lies towards the periphery and metaxylem lies towards the centre. Such arrangement of primary xylem is called (2)______
b. In (3)_______, the protoxylem lies towards the centre (pith) and the metaxylem lies towards the periphery. This type of primary xylem is called(4)______

 1345  253 Anatomy of Flowering Plants Report Error

Solution:

• In roots, the protoxylem lies towards the periphery and metaxylem lies towards the centre. Such arrangement of primary xylem is called exarch.
• In stems, the protoxylem lies towards the centre (pith) and the metaxylem lies towards the periphery. This type of primary xylem is called endarch.