It explains about what is plant tissue & both the types i.e meristem & permanent tissue. It also explains about the general characteristic, and how it has been classified based on origin, position, function and plane. It also furnish further information regarding the above

1. meristematic tissue
DR. C. BEULAH JAYARANI
M.SC., M.A, M.ED, M.PHIL (EDN), M.PHIL (ZOO), NET, PH.D (EDN)
ASST. PROFESSOR,
LOYOLA COLLEGE OF EDUCATION, CHENNAI - 34

2. Plant tissue
 Group or mass of cells that are similar in origin,
structure, function form a tissue.
 Plants are made up of vegetative and
reproductive part.
 In general plant tissues are classified into two types
namely.
1. Meristems
2. Permanent tissue
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4. meristematic tissue
 The term “meristem” means ‘divisible’ or
having cell division activity.
 Meristematic tissues are a group of
immature cells that are capable of
division.
 In plants meristem is found in three regions
where growth can take place for example
apex of stem, root, leaf etc..
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5. characteristics of meristematic tissue
 They are made of living cells.
 Cells are oval ,polygonal or round in
shape.
 They are thin walled with dense cytoplasm.
 They undergo mitotic division.
 They do not store food materials.
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6. tyPes of meristem
 1. Based on Origin and
development
 2. Based on position
 3. Based on function
 4. Based on plane of
divisions
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8. 1. origin and develoPment
 Based on origin and development they
are classified into three types:
1. Promeristem or primordial
meristem
2. Primary meristem
3. Secondary meristem:
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9. 1. Promeristem or
primordial meristem
 In plants they occupy a
small area at the tip of
root and shoot.
 They further divide to
form primary meristem.
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10. 2. Primary meristem
 They are present below
the promeristem at the
shoot and root apices.
 These cells divide to
form permanent tissues.
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11. 3. Secondary
meristem:
 It is derived from
primary
permanent
tissues which
have the capacity
of division.
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12. Based on Position
Apical meristem:
They are found at the apices of root
and shoot and bring about increase in
length. They include both promeristem
and primary meristem.
Intercalary meristem
It lies between the region of permanent
tissue and is part of primary meristem
which is formed due to intermittent
permanent tissues.
Lateral meristem:
these are arranged
to the parallel sides
of origin and
normally divide
radially to give
secondary
permanent tissues .
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13. functions
Protoderm: it is the outermost
layer of the growing region which
develop to form epidermis.
Pro cambium: it is composed of
narrow elongated cells that give
rise to vascular tissue.
Ground meristem: it is composed of
large thick walled cell which
develop to form hypodermis,
cortex and pith.
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14. Plane of division
 The growth pattern and
plane of division of
meristematic tissue is
important to govern the
mode of growth.
 Mass meristem
 Rib or file meristem
 Plate meristem
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15. Rib or file
meristem
cell division
occurs only on
one plane.
Mass meristem:
In this plane cell division
occurs in all planes resulting in
increase of volume. It can be
observed in meristems of cortex
and pith
Plate meristem:
These cells divide in two planes
resulting to an increase in the area of
an organ. Eg: leaf formation.
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16. REFERENCE
“BIOLOGY READER”
 Tamil Nadu text book
 NCERT Books
 Google Images
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