Parenchyma
Explanation
Simple permanent tissues in plants consist of cells that are structurally and functionally similar. They are primarily classified into three types based on the nature of their cell walls and intercellular spaces: Parenchyma, Collenchyma, and Sclerenchyma.
Option Analysis
- Parenchyma: This is the most common simple permanent tissue. It consists of living cells with thin cellulosic cell walls. A distinguishing feature of parenchyma is the presence of intercellular spaces between the cells, which facilitates gas exchange and storage.
- Collenchyma: This tissue consists of living cells that provide mechanical support and flexibility. The cells are thickened at the corners due to the deposition of cellulose, hemicellulose, and pectin. Intercellular spaces are generally absent.
- Sclerenchyma: This tissue consists of dead cells with thick, lignified walls. It provides structural strength and hardness to the plant. The cells are closely packed with no intercellular spaces.
- Cork: Cork cells are dead and compactly arranged without intercellular spaces. Their walls are coated with suberin, making them impervious to water and gases.
Key Takeaway: Parenchyma is the fundamental packing tissue in plants, characterized by thin cell walls and distinct intercellular spaces, unlike Collenchyma and Sclerenchyma which lack such spaces.