Practice question

Comparative wood anatomy distinguishes groups clearly: gymnosperm xylem dominated by tracheids with torus-margo bordered pits providing safety, lacking vessels except Gnetophytes where vessels evolved independently, resulting softwood with high embolism resistance but lower conductivity limiting leaf size. Angiosperm xylem combines tracheids, fiber-tracheids, libriform fibers, axial parenchyma and wide vessel elements bearing perforation plates simple or scalariform allowing efficient bulk flow supporting large leaves and high transpiration rates required for rapid growth. Presence of vessels alongside true sieve tube-companion cell complexes defines flowering plant vascular syndrome, despite secondary xylem production in both lineages providing mechanical strength.