The document discusses plant tissues. It defines tissue as a group of organized cells with common origin, function and structure. There are three main types of tissues in plants: meristematic, permanent and specialized tissues. Meristematic tissue is made of actively dividing cells found in growing regions and gives rise to permanent tissues through cell differentiation. Permanent tissues include epidermis, ground and vascular tissues which make up the basic structure of plants. Specialized tissues are further classified into external and internal secretory tissues.

1. WELCOME...

2. GENERAL IDEA
ABOUT
PLANT TISSUES
----PRESENTED BY
AINDRILA MAJUMDAR
[BIOTECHNOLOGY 2nd YEAR]

4.  THE LIFE OF AN ORAGANISM STARTS FROM A SINGLE CELL, WHICH IS THE
FERTILIZED EGG OR THE ZYGOTE. THIS SINGLE CELL UNDERGOES REPEATED MITOTIC
DIVISION TO FORM A MULTICELLULAR EMBRYO AND FINALLY THE ORGANISM
GRADUALLY DIFFERENTIATES.
THE FORMATION OF A MULTICELLULAR ORGANISM SHOWS THE FOLLOWING
ORGANIZATIONAL STAGES, (1)CELLS (2)TISSUE (3)TISSUE SYSTEM (4)ORGAN
(5)ORGAN SYSTEM(6)BODYOF ANORGANISM.
BUT IN UNICELLULAR ORGANISM, ALL THE PHYSIOLOGICAL FUNCTIONS ARE
CARRIEDOUTBYA SINGLE CELL, SO THIS ORGANIZATIONIS NOTOBSERVED.
IN HIGER PLANTS, TISSUE SYSTEMS ARE OF THREE TYPES: (1)EPIDERMAL (2)
GROUND(3)VASCULAR.

5. A TISSUE IS DEFINED AS A GROUP OF ORGANIZED
CELLS WITH A COMMON ORIGIN, FUNCTION AND
SIMILAR OR DIFFERENT STRUCTURES.

6. 1. Meristematic tissuecan be broadlyclassifiedon the
basis of origin,occurence,function and division.
2. Permanent tissue can besimpleor complex.
3. Specialtissue can be broadlyclassifiedinto external
secretoryandinternal secretory.It is actually apermanent
tissue.

7. The group of plant cells or tissue which is
in the active state of division is called
meristematic tissue or meristems. Consists
of small, cubodial densely packed cells with thin
cell walls & large nuclei, which keeps on dividing
to form new cells. Contain small vacuoles and
lack intercellular spaces. Capable of stretching,
enlarging and differentiate into other types of
tissues they mature. Remain young forever &
divide actively throughout the life of the plant.
Found in shoot & root tip, nodes, buds, between
xylem & phloem and so on. Gives rise to
permanent tissues.

8. Meristimatic tissue based on
occurance are:
1. Apical meristem
2. Intercalary meristem
3. Lateral meristem

9. APICAL MERISTEM
Present at the growing regions of the apex of the plant
organs. Found at the shoot apex, may also be found at the leaf
apices of developing leaves. Forms primary permanent tissue. Also
increases the longitudinalgrowthof plants.

10. INTERCALARYMERISTEM
The meristematic tissue that remain embedded within
the permanent tissue mainly between two nodes.
They remain in leaf base or at the lower internodes
of growing stem. They are formed because some
meristematic zones are left behined by the stem
during apical growth.
Functions of intercalary
meristem is to intiate
lengthwise growth of
the plant in addition to
the primary meristem.
Also forms permanent
tissue.

11. LATERAL MERISTEM
Present laterally on the axis of a plant. Occur
longitudinally on the lateral regions of roots
and stems mostly in two forms:
1. Fasicular cambium: The primary
cambium remaining within the vascular
bundles forming the secondary xylem and
phloem.
2. Phellogen or cork cambium: They are
extraxylary in position, noted during the
formation of bark of periderm. They are formed
of three layers,the lowermost living layer called
phelloderm, cutting off the upper cork cambium
or phellogen, which finally forms the outermost
scale bark or phellem, that are shedded off from
time to time.

12. MERISTEMATICTISSUE ON THE BASIS OFORIGIN
1. PROMERISTEM: PRESENT AT THE GROWING REGIONS OF
EMBRYO MAINLY SHOOT OR ROOT TIP OF A GROWING
SEEDLING. IT FORMS THE PRIMARY MERISTEM.
2. PRIMARY MERISTEM: REMAIN IN MERISTEMATIC STATE
THROUGHOUT THE LIFE CYCLE IN A PLANT. PRESENT IN
ROOT AND SHOOT APEX OF SEEDLING. INITIATES THE
FORMATION OF PRIMARY STRUCTURES IN PLANT.
3. SECONDARY MERISTEM: ORIGINATE FROM PRIMARY
MERISTEMS. FOUND IN VASCULAR REGION IN FORM OF
INTERFASCICULAR CAMBIUM. FORMS ANNUAL RING ALONG
WITH FASCICULAR CAMBIUM AND INITIATES CORTICAL
SECONDARY GROWTH.

13. 1. PROTODERM: OUTERMOST
MERISTEMATIC LAYER,WHICH
BY RADICAL DIVISION FORMS
THE EPIDERMAL TISSUE IN
THE STEM AND EPIBLEMA OR
THE PLIFEROUS LAYER IN
ROOT.
2. PROCAMBIUM: GIVES RISE TO
VASCULR TISSUES VIZ.
XYLEM,PHLOEM AND
CAMBIUM OF VASCULAR
BUNDLE.
3. FUNDAMENTAL OR GROUND
MERISTEM: THE TISSUE LIKE
CORTEX, PITH AND
MEDULLARY RAYS. OCCURS
IN BETWEEN PROTODERM
AND PROCAMBIUM. FORMS

14. 1. PLATE MERISTEM: HERE THE CELL DIVISION TAKES PLACE IN
TWO PLANES RESULTING IN THE INCREASE IN AREA.
OCCURS ON THE LEAF EPIDERMIS, CORTEX AND PITH.
CAUSES AN INCREASE IN AREA OF EPIDERMIS.
2. RIB MERISTEM: HERE THE CELL DIVISION TAKES PLACE IN
ONE PLANE. REMAINS IN THE VASCULAR BUNDLES OF
ROOT AND STEM. CAUSES INCREASE IN LENGTH OF
VASCULAR TISSUES.
3. MASS MERISTEM: DIVIDES IN ALL PLANES INCREASING THE
VOLUME OF CELLS. IT REMAINS IN THE ENDOSPERM,
CORTEX, PITH. HELPS IN THE FORMATION OF EMBRYO,
ENDOSPERM, CORTEX AND PITH. ACTS AS PACKAGING
TISSUE SERVING THE PURPOSE OF STORAGE AND
PHOTOSYNTHESIS.

15. THANK YOU...