Both collenchyma and sclerenchyma give mechanical strength to plants; ...
- Sclerenchyma are dead cells hence they don't possess protoplasm at maturity in the same way as phloem sclerenchyma have.
- But due to lignified cell wall at the corner, they are not able to expand more hence they don't lose protoplasm.
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Both collenchyma and sclerenchyma give mechanical strength to plants; ...
Sclerenchyma are dead cells hence they don't posses protoplasm at maturity in the same way as phloem sclerenchyma have
But due ti lignified cell wall at corner they are not able to expands more hence they don't lose protoplasm.
Both collenchyma and sclerenchyma give mechanical strength to plants; ...
Introduction:
Both collenchyma and sclerenchyma are types of plant tissues that provide mechanical strength and support to plants. However, they differ in certain characteristics, including the retention of protoplasm at maturity and the thickness of their cell walls.
Explanation:
The correct answer to the given question is option 'D', which states that both collenchyma and sclerenchyma retain the protoplasm at maturity and have uniformly thickened walls.
Retaining Protoplasm at Maturity:
1. Collenchyma: Collenchyma cells are living cells that retain their protoplasm at maturity. The protoplasm contains various organelles, including the nucleus, cytoplasm, and other cell components. This retained protoplasm allows collenchyma cells to continue their metabolic activities even after reaching maturity.
2. Sclerenchyma: Sclerenchyma cells, on the other hand, are dead cells at maturity. These cells have lost their protoplasm and other living contents during the process of cell maturation. As a result, sclerenchyma cells lack metabolic activities and primarily serve a mechanical function.
Uniformly Thickened Cell Walls:
1. Collenchyma: The cell walls of collenchyma cells are unevenly thickened. These thickened regions are often localized at the corners of the cell, providing additional support to the plant. The remaining cell wall areas are relatively thin.
2. Sclerenchyma: In contrast, the cell walls of sclerenchyma cells are uniformly thickened. These thickened cell walls are composed of a substance called lignin, which makes them rigid and provides strength to the plant.
Conclusion:
In conclusion, the primary difference between collenchyma and sclerenchyma lies in the retention of protoplasm at maturity and the thickness of their cell walls. Collenchyma cells retain their protoplasm and have unevenly thickened walls, while sclerenchyma cells lack protoplasm and have uniformly thickened walls. Both types of tissues contribute to the mechanical strength and support of plants.
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