Dorsiventral leaf (Dicots)

DORSIVENTRAL LEAF:



The dorsiventral leaves are found in dicots.

In the vertical section of dicot leaf there are mainly divided into three parts.
They are.

Epidermis
Mesophyll
Vascular Bundles


Epidermis:


The upper and lower epidermis of leaf is covered by cuticle.

The Adaxial(lower) surface has more number of Stomata than upper surface.Sometimes the upper surface lacks Stomata.


Mesophyll:


The layer present between the upper and lower epidermis is called as mesophyll.

It possess chloroplast and carry out photosynthesis.it contains parenchymatous cells.

Mesophyll is two types of parenchymatous cells.
    -Palisade parenchyma
    -Spongy parechyma

Polisade parenchyma is an elongated cell,arranged vertically and parallel to each other. present on upper side of mesophyll

Spongy parenchyma are oval or round loosely arranged situated below the palisade parenchyma extending to the lower epidermis. it contains air cavities.

Vascular bundles:


It is seen on the mid-ribs and veins of the leaves.

Size of the vascular bundles depends on the size of the veins.

Dicots contains Reticulate venation.

Vascular bundles are surrounded by Bundle sheath cells.

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