Multiple choice

Which one of the following activates cambium and elicites differentiation of xylem ?

  1. Abscisic acid

  2. Auxin

  3. Cytokinin

  4. Ethylene

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Auxin (IAA) is the primary hormone that stimulates vascular cambium activity and promotes differentiation of cambial derivatives into xylem (secondary growth). Cytokinins promote cell division but not specifically xylem differentiation. ABA inhibits growth; ethylene regulates fruit ripening and senescence.