Question

what happen to primary xylem during secondary growth​

Answer 1

Answer:

During the fall season, the secondary xylem develops thickened cell walls, forming late wood, or autumn wood, which is denser than early wood. This alternation of early and late wood is due largely to a seasonal decrease in the number of vessel elements and a seasonal increase in the number of tracheids.

Answer 2

Lateral meristems include the vascular cambium and, in woody plants, the cork cambium. ... The thickening of the stem that occurs in secondary growth is due to the formation of secondary phloem and secondary xylem by the vascular cambium, plus the action of cork cambium, which forms the tough outermost layer of the stem.