Page 76 - PG 101-Course notes مذكرة النظري 24-25 with spec
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Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD
2- Bicollateral:
Xylem occur between two patches of phloem on the same radius. One external
separated from the xylem by the cambium, the other internal separated from the
protoxylem by ordinary parenchyma. Such bundles occur in dicot stem.
3- Concentric: (One kind of vascular tissue completely surround one another).
a- Amphicribral: if phloem surrounds the xylem.
b- Amphivasal: if xylem surrounds the phloem.
3- Radial:
xylem and phloem patches are on different radii alternating with each other
(as in root). Each phloem strand is separated from adjacent xylem by parenchyma
cells
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