Secondary Meristems.pdf

Upward growth: Primary growth Downward growth: Primary growth Outward growth: Secondary growth Vascular cambium Secondary meristem-an example • The vascular cambium produces new conductive tissues (secondary xylem and secondary phloem) • Vascular cambium_cells other than the apical meristem that...

Upward growth: Primary growth Downward growth: Primary growth Outward growth: Secondary growth Vascular cambium Secondary meristem-an example • The vascular cambium produces new conductive tissues (secondary xylem and secondary phloem) • Vascular cambium_cells other than the apical meristem that undergo cell division • Increase the girth of stems and root of all gymnosperms and many angiosperms =fasicular cambium + interfasicular cambium Seondary growth: Secondary xylem Secondary phloem From vascular cambium Meristematic cells in cambium Pine Stem Tree Rings • Vascular Cambium Secondary xylem and phloem Auxin signaling and lateral root formation • • • • NAA Nitric oxide (NO) Sodium nitroprusside (SNP) CPITO (destroys NO) 1-Naphthalene acetic acid Lateral Root Initiation cortex pericycle Nitric oxide (NO)