What is venation? Give its types.

Veins in plants consist of phloem and xylem cells, which are embedded in parenchyma and sometimes in sclerenchyma. These veins are surrounded by bundle sheath cells. The phloem in the veins transports sugar from the leaf to the rest of the plant, while the xylem transports water from the petiole to the lamina mesophyll.

Venation refers to the arrangement or pattern of veins and veinlets on the leaf blade. It plays a vital role in distinguishing and identifying plants, as well as providing coordination, protection, and support for plant growth. There are two main types of venation:

1. Parallel Venation:

In parallel venation, the veins are arranged parallel to each other across the leaf blade. This type of venation is found in monocot plants. Examples of plants with parallel venation include:

• Bamboo
• Wheat
• Grass
• Banana
• Maize

2. Reticulate Venation:

In reticulate venation, the veins form a network-like or web-like pattern across the leaf blade. This type of venation is characteristic of dicot plants. Examples of plants with reticulate venation include:

• Mango
• Hibiscus

Additional Information:

Parallel venation can be further divided into two types based on the presence of the midvein:

1. Pinnate Parallel Venation: In this type, veins arise from the midrib (the central vein) of the leaf, extending from the base to the apex. The veins grow perpendicular to the midrib and parallel to each other. This is also called unicostate parallel venation. An example is banana.
2. Palmate Parallel Venation: In this type, the veins are parallel but have multiple primary veins originating from a common point. It is also known as multicostate venation. An example is grass.