Page 63 - PG 101-Course notes مذكرة النظري 24-25 with spec
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Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD
Tracheary Atracheary
A) Tracheids
▪ They are conducting elements and serve also for support. A) Xylem fibers
▪ Each tracheid is a single, elongated cell ▪ Hard, thick lignified
originates from one procambial cell with bluntly tapering ends. walls.
▪ At maturity is a dead element and its wall hard, normally lignified. ▪ Longer and narrower
▪ Pitted with imperforated tapering ends. ends and more
▪ In gymnosperms, the xylem is formed mainly of tracheids and no vessels. tapering than
tracheeids
▪ Have simple pits
✓ Function:
mechanical support.
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