Structure Of Leaf

Internal structure of leaf shows the upper and lower epidermis covered by a thin layer called cuticle. In between these two epidermal layers, mesophyll tissue is present which is of two types: 

palisade parenchyma; present below the upper epidermis. The cells of palisade tissue are long cylindrical containing more chloroplasts for carrying out photosynthesis. 
Spongy parenchyma; present above the lower epidermis and the cells are loosely packed with large intercellular spacesto store food. 
Stomata are located in the lower epidermis. A large number of chloroplasts are present in the guard cells of stomata and ground tissue of plants. 

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