Give one word equivalent for the following :
(i) A plant tissue that consists of cells which continue to divide to produce
more cells.
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(ii) The meristematic tissue responsible for the increase in thickness of the
stem of a tree.
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(iii) The kind of plant tissues which consists of all similar cells.
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(iv) The category of plant tissues in which the cells do not divide.
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Answers
Answer:
1)Meristematic tissue
2)There are three meristemetic tissue: Apical meristem, intercalary meristem and cambium or lateral meristem. First of all breadth and girth is the same thing. The tissue which is responsible for the increament of girth of the stem and root is cambium or lateral meristem.
3)A group of cells which are similar in origin; similar in structure and similar in function are called simple permanent tissue. They are of three types: Parenchyma. Collenchyma.
4)Plant tissue in which cell do not divide - permanent tissues ( parenchyma ,collenchyma, sclerenchyma etc.)
1) Meristematic tissue
*Meristematic tissue (Greek:meristos-divisible) is a simple plant tissue of thin walled embryonic cells.
*It undergo mitotic division to form new cells and tissues.
*Cells of Meristematic tissue are isodiametric in shape (with prominent nuclei and dense cytoplasm).
*They exhibit a high metabolic activity.
*Meristematic cells form two type of cells:initiating cells and permanent cells.
2) Lateral meristem
*The Meristematic tissue responsible for the increase in thickness of the stem of a tree is lateral meristem.
*They are responsible for lateral growth of the plant that is, increase in girth or diameter.
*The examples for lateral meristems are vascular cambium and cork cambium.
*It divides only periclinally or radially .
3)Simple permanent tissue
*Simple permanent tissue consists of a group of uniform cells.
*The cells are similar in structure and carry out same function.
*They can be classified into three:
•Parenchyma: commonest simple
tissue.Arranged loosely with
intercellular space.
•collenchyma:living,simple,
mechanical tissue.Thickening of cell
wall at the corners.
•sclerenchyma:simple dead and
mechanical tissue.highly thickened
cell walls.
4) Permanent tissue
*Permanent tissue are those tissue which have lost the power of cell division.
*Cells of permanent tissue are matured,assume a definite shape ,size and function.
*On the basis of constituents cell permanent tissues are classified into three types: simple tissues,complex tissues and special tissues.