What are palisade cells? What functions do they serve? - …

Leaves that develop in sunny environments and have high photosynthetic capacities are generally thicker than leaves from shaded environments. This is achieved with more elongate cells within the palisade layer and/or several layers of cells forming the palisade tissue. Thicker leaves in a sunny environment enable more Rubisco to be deployed which confers a higher photosynthetic capacity. Fitting more Rubisco into a unit of leaf area with good access to intercellular airspace requires an increase in mesophyll cell surface which is possible by increasing the thickness of the mesophyll tissue and hence leaf thickness. A thicker leaf in sunny environments is energy effective because enough photons reach chloroplasts in lower cell layers to keep their Rubisco gainfully employed. By contrast, in a shaded habitat, less Rubisco is required for a leaf with lower photosynthetic capacity and this can be fitted into thinner leaves.

What are palisade cells? What functions do they serve? …

Photosynthesis mainly takes place in the palisade mesophyll cell in the leaves of plants.

what is the function of a palisade mesophyll cell

, (2009) Green light drives leaf photosynthesis more efficiently than red light in strong white light: Revisiting the enigmatic question of why leaves are green. Plant Cell Physiol 684-697

palisade and spongy layers is known as the mesophyll.

Excellent fluorometers for use in laboratory and field such as the Plant Efficiency Analyser (Hansatech, King’s Lynn, UK) make accurate measurements of all the indices of the Kautsky curve and yield rapid information about photochemical capacity and response to environmental stress. Conventional fluorometers (e.g. Figure 1.15) use a given source of weak light (commonly a red light-emitting diode producing only 50–100 µmol quanta m–2 s–1) for both chlorophyll excitation and as a source of light for photosynthetic reactions.

Note that the cells of the spongy mesophyll are loosely and some­whathaphazardly arranged.
The mesophyll cells contain palisade cells, which are located beneath the upper epidermis....

Palisade mesophyll cell : light:

Below the epidermiscells the palisade mesophyll consists of three or four overlappinglayers of cells, which are fairly loosely packed, allowing for gases to enterfrom the upper epidermis.

In the corn leaf, the mesophyll cells surround the bundle sheathcells.

The palisade mesophyll tissue is a layer of cells in a leaf

Figure 1.2 A scanning electron micrograph of an uncoated and rapidly frozen piece of tobacco leaf fractured in (A) to reveal columnar mesophyll cells of the palisade layer beneath the upper leaf surface and spongy mesophyll in the lower half. Chloroplasts can be clearly seen covering the inner faces of cell walls. Looking onto the lower surface (B), the epidermis and stomata are present on the left side of the vein, whereas the epidermis was fractured away on the right side, revealing spongy mesophyll tissue. Light micrographs (C, D) of sections cut parallel to the leaf surface are shown for palisade (C) and spongy mesophyll (D) with solid lines showing where the paradermal sections align with (A). Chloroplasts form a dense single layer covering the cell surfaces exposed to intercellular airspace, but are rarely present lining walls where two cells meet. Scale bar in (A) = 50 µm and (B) = 200 µm. (C) and (D) have same magnification as (A). (Images courtesy J. Evans and S. von Caemmerer)

Only the light reactions of photosynthesis occur in the chloroplasts ofthe mesophyll cells.

multiple palisade and spongy mesophyll layers



The products of photosynthesis, although initially carbohydrates, are
rapidly fed into other biochemical pathways to produce amino acids and
lipids for the requirements of the cells of the plant.