Page 141 - Ultimate Visual Dictionary (DK)
P. 141

PHOTOSYNTHESIS
        CROSS-SECTION THROUGH LEAF
        Christmas rose
        (Helleborus niger)                                       Cuticle (waterproof  covering)

              Upper (adaxial)
                                                                                           Cell wall
              epidermis (outer
              layer of  cells)
                                                                                           Cytoplasm
                                                                                            Vacuole
                                                                                            Chloroplast
           Palisade mesophyll                                                               (photosynthetic
           (tightly packed layer                                                            organelle)
           of  photosynthetic
           tissue)                                                                          Nucleus
                                                                                             Intercellular
                                                                                             space

                                                                                               Sclerenchyma
                                                                                               (strengthening
                                                                                               tissue)
                                                                                               Xylem (tissue
                                                                                               that transports
                                                                                               water and
                                                                                               mineral salts)
           Spongy mesophyll
           (loosely packed layer                                                               Phloem (tissue
           of  photosynthetic                                                                  that transports
           tissue)                                                                             sugars and
                                                                                               other nutrients)
                                                                                             Vein




              Lower (abaxial)
              epidermis (outer
              layer of  cells)                                                               Parenchyma
                                                                                             (packing
                       Guard cell                                                            tissue)
                       (controls opening   Stoma
                       and closing of    (pore)     Substomatal
                       stoma)                       chamber
        INTERNAL VIEW OF CHLOROPLAST
                                                       Lamella
                       Granum                          (membrane of         Thylakoid
                       (stack of  thylakoids that      thylakoid)           (flat sac of
                       hold chlorophyll                                     granum)
                       molecules in position)
                                                                                      Deoxyribonucleic
                   Stroma                                                             acid (DNA)
                   (watery matrix)                                                    strand

                    Outer                                                                 Starch grain
          Chloroplast   membrane
          envelope
                    Inner
                    membrane

                                                                                         Stroma thylakoid
                     Ribosome                                                            (link between grana)
                     (site of  protein
                     synthesis)


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