Question

Define venation.

Answer 1

Venation is the appearance of the arrangement of veins in the lamina of the leaf surface. This type of arrangement is found in leaf tissues.

Complete answer:
The process of vein formation on the leaf is known as venation. There are three types of venation namely Reticulate venation, Parallel venation and Furcate venation. When the veins are designed in either web-like or network-like all across the lamina, it is known as reticulate venation. It combines irregular vein arrangement for the creation of a network. This feature is found on the leaves of dicot plants. Examples: Hibiscus papaya, leaves of Tulsi, Coriander, China Rose, Mangifera. When the veins are organised parallel to one another all over the lamina, it is known as parallel venation. In parallel venation, veins originate from the midrib and run parallel. Which means that the veins go parallel to each other. This is found in leaves of monocot plants.
When veins form dichotomous branching it is known as furcate venation as seen on leaves of a fern.

An example of pinnate reticulate venation is seen on a mango leaf. It is identified as an appearance of a central midrib and a bunch of small veins beginning from the midrib. It spreads all over the leaf and it is the common type of venation.

An example of parallel venation is seen on the banana leaf. The cell of the leaf requires a supply of nutrients. This venation is providing sufficient nutrients to the plant.

Note: Reticulate venation is sub-classified into two types of venation namely Pinnate Reticulate and Palmate Reticulate. Similarly, parallel venation is subdivided into Pinnate parallel and Palmate parallel.