Palm Trees and Cycads Have Converged on a Similar Growth

Palm trees and cycads have converged on a similar growth form, yet they actually grow and develop quite differently. What are some of these similarities and differences?

A) Cycad stems are composed mostly of a mantle of roots.
B) Palms lack a vascular cambium, but cycads do not.
C) Cycads have sheathing leaf bases that protect their apical buds, whereas palm apical meristems are protected by bud scales.
D) Neither produces vegetative branches as part of normal growth.