Anatomy of the Leaf

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Anatomy of the Leaf And Transpiration
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Leaves are the primary site of photosynthesis in
a plant. Three kinds of layers makes up a leaf 1.
Epidermis outer layer 2. Mesophyll Middle
layer 3. Vascular bundles Transports Materials
through the mesophyll
Cross section of a leaf
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Transport in Plants
Veins are the basic structure of transport in the
plant. 1. H2O and minerals need to move from
the root system to the rest of the plant
(xylem) 2. Sugar needs to move from the leaves
to storage area and other places energy is
needed in the plant (phloem)
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Transpiration Pulls Water Up in A Plant
Transpiration is the loss of water vapor from a
plant. occurs through the stomata -the stomata
can open for gas exchange in photosynthesis
(CO2/O2) -Loss of water vapor creates suction
drawing water up through the xylem from the
root system - like a straw -90 of water taken
in by the roots is lost through the leaves
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regulated by the guard cells -stoma opens and
closes because of water pressure within the
guard cells -high water pressure causes the
cells to bow and the stoma to open the
inside edge of the cell is thicker causing the
cell to bow when it swells with water -low
water pressure causes the cell to relax and
the stoma to close
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Stomata