State the characteristics of collenchyma tissue?
1. it is a living tissue, thin cell walls but thicken at the corners.
2. little intercellular spaces are present.
3. occurs below the epedimes in leaf stocks.
4. extra cellulose and bacteria deposits are there. they also contain at times in chlorpplasts.
1. its a machenical tissue gives machenical support,elesticity to plants .
2. flexibility to the organs as it is present in parts which can bent.
3. early bending in various parts of plants contain chloroplast that manufacture food.
Collenchyma - found just below the epidermis in petiole (e.g. celery stalks), leaves, and young stems; usually specialized; characteristics include:
living at maturity
irregularly thickened cell walls (+cellulose)
plastic (can change shape but do not usually return to the original shape; remain deformed)
some involvement in transport of nutrients
Sclerenchyma - in mature parts of the plant, especially in woody plants and herbaceous perennials; specialized; characteristics include:
dead at maturity - protoplast is absent
very thick, sclerified cell wall (+lignin)
impermeable to water and other nutrients
in cells specialized for transport of water and nutrients, the cell wall contains holes called pits.
transport of water and nutrients
Specific examples of
fibers - long and slender
sclerids (stone cells) - relatively spherical; the gritty texture of pears is due to the presence of stone cells.