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11. Homeostasis eLearn.Punjab
Recalling
Transpiration is the loss of water from plant surface in the form of vapours.
Guttation is not to be confused with dew, which condenses from the atmosphere onto the plant
surface.
11.1.3 Removal of Other Metabolic Wastes
Plants deposit many metabolic wastes in their bodies as
harmless insoluble materials. For example, calcium oxalate
is deposited in the form of crystals in the leaves and stems
of many plants e.g. in tomato (Fig. 11.2).
Figure 11.2: Calcium oxalate
needles in a leaf cell
The removal of excretory products is a secondary function of leaf fall. If the leaves are not shed,
the calcium oxalate just remains as harmless crystals in the leaves
In trees which shed their leaves yearly, the excretory products are removed from body during leaf
fall.
Other waste materials that are removed by some plants are resins (by coniferous trees), gums (by
keekar), latex (by rubber plant) and mucilage (by carnivorous plants and ladyfinger) etc. (Fig. 11.3).
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