chloroplasts near to edge of cell to... absorbmorelight
cylindrical shape= larger surfacearea
their thin walls allow light to penetrate easily into the leaf, so that photosynthesis can take place efficiently.
palisade mesophyll cells are cylindrical because they have a large surface area which allows them to absorb lots of carbon dioxide from air spaces between leaves.
large vacuole to store sugar and starch
thin cell walls to let light through
large number of chloroplasts to increase rate of photosynthesis
long and narrow gaps between palisade cells for air to circulate for gas exchange