Page 75 - PG 101-Course notes مذكرة النظري 24-25 with spec

Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD

Types of V.B.

❖ The phloem and xylem are associated with each other within V.B., the
variation in the arrangement of these vascular tissues in the bundles have

led to the establishment of different bundle types.
1- Collateral: phloem outside and xylem inside (on the same radius).

a) Open collateral (V.B). b) Closed collateral (V.B.)

Here phloem is outside, and xylem is The same as type collateral V. B,
inside and they are located on the same but there is no cambium, and the bundle
radius and cambium is in between. looks alike skull shape.
The xylem arrangement is endarch The xylem arrangement is endarch in
form of Y- shape
-Surrounded by bundle sheath

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