Palisade mesophyll

  • Title

    Palisade mesophyll

  • Definition

    Referring to one or more layers of cells located directly under the epidermal cells of the adaxial leaf blade surface. The palisade mesophyll is oriented vertically and is longer than broad. Photosynthesis takes place in both palisade and spongy mesophyll.

  • Notes

    There is considerable variation in the ratio of palisade to spongy mesophyll, e.g., some leaves of some species may appear to have all palisade mesophyll and others all spongy mesophyll. In addition, this ratio may vary in the same tree depending upon whether the leaves are exposed to the sunny conditions of the top of the canopy or the darker conditions of the middle and lower parts of the canopy.

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