Describe the internal structure of a dicot leaf.
Diagram not necessary )

Explanation

Epidermis:
1. this leaf is generally dorsiventral. It has upper and lower epidermis.
2. The epidermis is usually made up of a single layer of cells that are closely packed.
3. The cuticle on the upper epidermis is thicker than that of lower epidermis.
4. The minute openings found on the epidermis are called stomata.
5. Stomata are more in number on the lower epidermis than on the upper epidermis.
6. A stomata is surrounded by a pair of bean shaped cells called guard cells.
7. The main function of the epidermis is to give protection to the inner tissue called mesosphyll.
8. The cuticle helps to check transpiration.
Stomata are used for tanspiration and gas exchange.
Mesophy II
1. The entire tissue between the upper and lower epidermis is called the mesophyll
2. two regions in the mesophyll (i) palisade parenchyma , (ii) spongy parenchyma.
(i). Palisade parenchyma cells:
1. Seen beneath the upper epidermis.
2. Consists of vertically elongated cylindrical cells in one or more layers.
3. Cells are compactly arranged and generally without intercellular spaces.
4. Contains more chloroplasts than spongy parenchyma cells
5. Funtion is photosynthesis.
(ii) Spongy parenchyma cell:
1. Lies below the palisade parenchyma.
2. Cells are irregularly shaped and very loosely arranged with numerous airspaces.
3. Facilitate the exachange of gases with the help of air spaces.
4. The air space that is found next to the stomata is called respiratory cavity or substomatal cavity.
Vasculary Tissures
1. Vascular tissues are present in the veins of leaf.
2. Vascular bundles are conjoint, collateral and closed.
3. Xylem is present towards the upper epidermis ,while the phloem towards the lower epidermis.
4. Vascular bundles are surrounded by a compact layer of parenchymatous cells called bundle sheath or border parenchyma.