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



                               Anatomy Summary




                  Items              dicot stem                      monocot stem
                  Stomata           Dicot stomata if present         Monocot stomata if present
                  Hypodermal layer  May be all of types of ground tissues  Mostly sclerenchyma
                  Cortex and pith   Found                            Not found
                  V. B.             Open or bicollateral             Closed collateral

                        Items                   Dicot leaf                 Monocot leaf

                      Stomata       Dicot stomata type                Monocot stomata
                     Epidermis      polygonal or polyhedral cells     Usually, elongated cells
                   Palisade and spongy   Present                      Absent
                        V. B.       Open or bicollateral              Closed collateral

                        Items                            Dicot root                                              Monocot root
                      Epidermis
                   (piliferous layer)         Consists of a single layer of parenchyma, has no cuticle, no stomata, outer wall may be extended into root hair.
                       Cortex                        Mostly parenchyma                                   Some of it may be sclerenchyma
                                          Deposition of lignin and suberin in radial walls   Deposition of lignin and suberin in radial walls and inner tangential
                   Casparian strips
                                                            only                                                     walls
                                         Fewer number (2-8) of the radial type with exarch   Numerous (more than 8) of the radial type with exarch xylem
                        V. B.
                                                      xylem arrangement                                           arrangement
                         Pith                          Narrow or absent                      Very wide (well developed) and consists of parenchyma cells.

                                         Palisade              Spongy           Spring wood      Summer wood
                  Location      Perpendicular to the epidermis   Scattered    ■ Is wider       ■ Much denser
                                formed of one or more layers                  ■        Bigger  ■         Narrow
                  Shape         Elongated (columnar) cells    Irregularly     proportion   of  elements,  mainly
                                                             shaped cells     vessels  and  less  fibers  and  less

                  Intercellular  Narrow                      Wide (for gas    fibers           vessels.
                  spaces                                     exchange)        ■ Vessels wider,  ■  More  thickened
                  Chloroplasts  Abundant                     Less             less  thick  wall,  and lignified walls
                                                                              less lignified.   and small lumen.
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