Q- (a) Enlist the position, nature of cells and functions of three types of simple permanent tissues of plants.
(b) In which characters, meristematic tissue is different from permanent plant tissue.
Answer- (a) The Simple permanent tissue is mainly of three types:
Parenchyma are mainly found in most soft parts of the plant such as: epidermis, cortex, endodermis, pericycle, pith of roots of plants or trees. Parenchyma is thin walled and living tissue. Parenchyma is responsible for many important functions in the plant but the main function of parenchyma is to store food (such as starch grains in the parenchymal cells of potato tuber).
Collenchyma are mainly found in hypodermis of dicot stem and also found in midrib and leaf stalks of plants or trees. Collenchyma is thick walled and living tissue. Collenchyma is responsible for many important functions in the plant but the main function of Collenchyma is to provide mechanical support to the plant or tree. It also allows plants to bent easily that prevent them from being uprooted by high velocity wind.
Sclerenchyma are mainly found in the hypodermis of monocot stem, husk of coconut, covering of seeds and nuts in in the veins of leaves around vascular bundle. Sclerenchyma is thick walled and dead tissue. Sclerenchyma is responsible for many important functions in the plant but the main function of Sclerenchyma is to provide the plant mechanical support (chief mechanical tissue), so also enables the plant to resist various strains.
(b) The Meristematic tissue are different from permanent tissue is several ways. Some of the main difference between meristematic and permanent tissue are as follows:
1. The Meristematic tissues do not did cell division throughout the life while the permanent tissue do not did cell division throughout the life as they did cell division for a limited time period.
2. The Meristematic tissues are responsible for the growth of plant or tree as meristematic tissues do not did cell division throughout the life while the permanent tissue are not responsible for growth of plant or tree they did cell division for a limited time period.
3. Meristematic tissues are thin walled and their cell wall is formed of cellulose on the other hand the permanent tissue have either thin or thick cell wall which is formed of pectin.
4. Meristematic tissue is round, oval or polygonal shaped whereas permanent tissues are polygonal, rounded, oval and fibre-like structure.
5. The cytoplasm of meristematic tissue is non-vacuolated whereas the cytoplasm of permanent tissue is vacuolated whereas the cytoplasm of permanent tissue is vacuolated.
6. Intercellular space is present in meristematic tissue while intercellular space is not present in permanent tissue.