Q. In (i) protoxylem lies towards periphery and metaxylem lies towards centre. Such an arrangement of primary xylem is called as (ii).
(i) (ii)
(a) stems endarch
(b) stems exarch
(c) roots endarch
(d) roots exarch

 5960  176 Anatomy of Flowering Plants Report Error

Solution:

In exarch condition of xylem, protoxylem or the first formed xylem is present towards the periphery while metaxylem or later formed xylem is present towards the centre of the root. Such an arrangement can be seen in roots.