can u tell me the significance of protoxylem being endarch or exarch in a vascular bundle?

Question

whats the significance of it? how does it influence the physiology?

Answer 1

Neraj is very confused.

"Protoxylem is primary xylem [true]. It is the first xylem tissue formed in the actively dividing vascular cambium of a young plant [no, it's produced by the procambium].

Protoxylem is secondary xylem [no. it's primary xylem]. It is formed by secondary growth from the actively dividing vascular cambium [no, see above] ."

Endarchy and exarchy refer to the direction of maturation of the protoxylem. Roots are exarch....the outer protoxylem matures first. Shoots are endarch...the inner protoxylem matures first.

Answer 2

Protoxylem is primary xylem. It is the first xylem tissue formed in the actively dividing vascular cambium of a young plant.

Protoxylem is secondary xylem. It is formed by secondary growth from the actively dividing vascular cambium. The cell walls of protoxylem are thickened by a deposit of lignin, providing mechanical support to the plant.