Differentiate between:-
a Parenchyma and collenchyma
b Meristematic and permanent tissue
c Sclerenchyma and parenchyma.
Answers
Answer:
BASIS FOR COMPARISON PARENCHYMA COLLENCHYMA SCLERENCHYMA
Meaning
The living plant cells are originating from ground and protoderm meristem. These type of cells are most abundantly found in plants tissue. The type of living plant cells originating from the pro-cambium. The epidermal layers of the plant are made of collenchyma cell.
---‐--------
The hard and outer part of the stem is made up of the sclerenchyma cells. These are the dead plant cells which originate from ground meristem and protoderm procambium.
Found in
These type of cells are present in every soft part of the plant. These cells are found in specific part of the plant like leaves, stems, and petioles. It is found in mature parts of the plants or trees.
Type of cell
Unspecialized and living cells.
Specialized cells and living cells.
Specialized, matured and dead cells.
Cell Shape
There are various shapes of the cells, but generally, they are isodiametric. Elongated cells are present.
Sclereids, elongated and fibre shape.
Cell wall
Thin cell wall present. Uneven cell wall. Hard and thick cell wall present.
The cell wall is made up of cellulose.
The cell wall is made up of pectin and hemicellulose.
The cell wall is made up of lignin.
Intercellular space between the cells Present.
Less space is present between the cells.
Absent and so cells are tightly packed.
Function
Parenchyma cells help in storage of foods, in gaseous exchange, and in photosynthesis. Collenchyma cells provide mechanical support and elasticity to the plant. Sclerenchyma cells provide mechanical support to the plant. It also supports transportation of water and nutrients to the plants.
Explanation:
(a) Parenchyma Cells
These are the living plant cells known to repair and heal and also to store food, forms a thin layer known as primary cell wall of the plant. They occur as a continuous mass, widely distributed from stems, roots to leaves and fruits
Generates other special cells and tissues
Isodiametric in shape, having thin cell walls hence experience pressure and force around the cells, therefore, cells increase its volume capacity to equalize all-over pressure on the cells
Cells composed of cellulose and hemicellulose
Show abundance in cell organelles such as – Golgi bodies, ribosomes, Chloroplast, Endoplasmic Reticulum, and other constituents such as pigments, fats, starch, proteins.
Collenchyma Cells
Known to render mechanical support to plants by protecting the delicate inner structure of plants
They have thick cell walls composed of cellulose, hemicellulose and pectin and are living cells. Cells comprise of prominent nucleus and organelles
It carries out storage of food, checks for the tearing of leaves, carry out photosynthesis. They also push the organs of plants thus aiding in growth and elongation
(b)
DIFFERENCES BETWEEN MERISTEMATIC TISSUE AND PERMANENT TISSUE:-
•Meristematic tissues have capacity to divide qhere permanent tissue do not have.
•Meristematic tissue have thin cellulose wall whereas permanent tissue has thick cellulose wall.
•Meristematic tissue do not have intercellular space whereas permanent tissue has large intercellular space.
•Meristematic tissues are responsible for the primary and secondary growth of the plants whereas permanent tissue is responsible for various growths.
•Meristematic tissue has dense cytoplasm with prominent nucleus whereas permanent tissue has thin cytoplasm with normal nucleus.
•Meristematic tissues have many small vacuoles in their cytoplasm whereas permanent tissue contain only single large vacuole in their cytoplasm.
♦Hope it helps♦
(c) Parenchyma:
(1) Cells are thin walled and unspecialised. (2) These are living cells. (3) Cells are usually loosely packed with large intercellular space. (4) Stores nutrients and water in stem and roots. (5) Some cells contain chlorophyll, called as chlorenchyma and perform photosynthesis. Other cells have large air cavities, called as aerenchyma, which provide buoyancy to the hydrophytic plants.
Sclerenchyma:
(1) Cells are thick walled and lignified. (2) Tissues are made up of dead cells. (3) No intercellular spaces between the cells are found. (4) Provides strength to the plant parts. (5) The cells are long and narrow, make the plant hard and stiff. The tissue is present in the stem around vascular bundles, in veins of leaves and hard covering of seeds and nuts.
Hope it'll help u.....