Question

Describe the internal structure of a dorsiventral leaf with the help of labelled diagrams.

Answer 1

Dorsiventral leaves are found in dicots. The vertical section of a dorsiventral leaf contains three distinct parts.

[1] Epidermis:

Epidermis is present on both the upper surface (adaxial epidermis) and the lower surface (abaxial epidermis). The epidermis on the outside is covered with a thick cuticle. Abaxial epidermis bears more stomata than the adaxial epidermis.


[2] Mesophyll:

Mesophyll is a tissue of the leaf present between the adaxial and abaxial epidermises. It is differentiated into the palisade parenchyma (composed of tall, compactly-placed cells) and the spongy parenchyma (comprising oval or round, loosely-arranged cells with inter cellular spaces). Mesophyll contains the chloroplasts which perform the function of photosynthesis.

[3] Vascular system:

The vascular bundles present in leaves are conjoint and closed. They are surrounded by thick layers of bundle-sheath cells.

Hope this will help you ......✌

Answer 2

Internal structure of dicot leaves is described below :

1. Epidermis

In the upper epidermis, chloroplasts are not found in them. Also, stomata is present in less number.

In the lower epidermis, we can find large numbers of stomata.

2. Mesophyll

It is the tissue present in leaf where the photosynthesis takes place.

3. Vascular System

In dicot leaves, we can observe thick type of vascular bundles in the veins that are thicker and smaller kind of vascular bundles in the veins that are thinner.