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Collenchyma tissue Cell structure

Collenchyma tissue Cell structure

Collenchyma tissue
Collenchyma tissue

The parenchyma cells with uneven angular thickening which support the young growing part of the plant are called collenchyma.


Cell structure and organization


These cells have a living protoplast. They are simple tissues & contain a single type of cells. Collenchyma cells have pointed & prismatic elongated end tips. They provide further growth and divisions. Collenchyma tissue also contains chloroplasts in green organs.

Presence


Collenchyma tissue are present in the margin of leaves.

Presence of cell wall in collenchymatous cells


The thickened primary wall is non-lignified. Mostly, it is composed of cellulose. Therefore, it shows elasticity in nature. The angular thickening are rich in cellulose. The additional layer of microfibrils is also present inside the wall.

Sclerification


In some cases, the cell wall of Collenchyma is sclerified. Sclerification occurs by the formation of the lamella. The lamella is rich in cellulose.

Size and shapes


Different collenchyma tissues have different sizes and shapes. Mostly, these cells are elongated with tapering ends. The largest type of Collenchyma tissues are present in the central position. In the periphery, shorter collenchyma tissues are present.

Types of Collenchyma tissue


1. Angular collenchyma


Angular collenchyma is present in the petioles of some plants.

2. Lamellar collenchyma


These collenchymatous cells are present in the stem cortex of some plants.

3. Lacunar collenchyma


They are present in the petiole of composite species.

Types of Collenchyma tissues

Functions of Collenchyma tissue

1. Elasticity

It has elasticity. So they provide mechanical support to plants.

2. Support

Collenchyma tissue is present in herbaceous plants. And provide support to such weak plants.

3. Photosynthesis

Some collenchyma contains chloroplast. So they are called photosynthetic.

4. Support to leaf

They are present around the vascular bundle of the leaf. So they provide support to leaf tissues.

5. Bundle sheath and bundle caps

They form bundle caps and bundle sheath in leaves.

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