The document discusses plant tissues. There are two main types of plant tissue - meristematic and permanent tissue. Meristematic tissue is dividing tissue found at growth points that allows plants to grow. It includes apical, lateral and intercalary meristem. Permanent tissues are non-dividing and include simple tissues like parenchyma, collenchyma and sclerenchyma, as well as complex tissues like xylem and phloem that transport materials.

1. Tissues chapter 2

2. THE CELL IS THE STRUCTURAL AND
FUNCTIONAL UNIT OF LIFE. EVERY
ORGANISM IS MADE UP OF CELLS.
CELLS COMBINE TO FORM TISSUE.
THE TERM TISSUE WAS COINED BY
BICHAT IN 1792.
THE STUDY CELL IS CALLED AS HISTOLOGY.
THE PLANTS AND ANIMALS ARE MADE UP
OF DIFFERENT TYPES OF CELLS WHICH
COMBINE TO FORM TISSUE.
TISSUE

3. PLANT TISSUE
THE TISSUE PRESENT IN THE PLANTS
IS CALLED PLANT TISSUE. THE PLANT
TISSUE IS OF TWO TYPES:
a. MERISTEMATIC TISSUE
b. PERMANENT TISSUE.

4. CLASSIFICATION OF PLANT
TISSUE

5. MERISTEMATIC TISSUE
THE MERISTEMATIC TISSUE DIVIDE
CONTINIOUSLY AND HELP IN
INCREASING THE LENGTH AND
GIRTH OF THE PLANT.
CHRACTERSTICS OF MRISTEMATIC
TISSUE
THEY ARE SIMILAR IN STRUCTURE
HAVING A THIN WALL OF CELLULOSE.
THEY MAY BE SPHERICAL , OVAL ,
POLYGONAL RECTANGULAR IN SHAPE.
THEY ARE COMPACTLY ARRANGED.
THE MERISTEMATIC CELLS CONTAIN

6. TYPES OF MERISTEMATIC TISSUE ON BASIS
OF POSITION
APICAL MERISTEMS
LATERAL MERISTEM
INTERCALARY

7. TYPES OF MERISTEMATIC TISSUE ON
BASIS OF POSITION

8. APICAL MERISTEM
 IT IS SITUATED AT THE TIP OF STEM AND
ROOT.
THE APICAL MERISTEM WHICH IS
PRESENT AT THE TIP OF STEM
CONSTITUTE SHOOT APEX. THE APICAL
MERISTEM WHICH IS PRESENT AT THE TIP
OF ROOT CONSTITUTE ROOT APEX.
APICAL MERISTEM IS ALSO FOUND IN THE
APICES OF THE LEAVES.
LATERAL MERISTEM
IT IS FOUND BENEATH BARK AND
VASCULAR BUNDLES OF DICOT
ROOTS AND STEM.

9. INTERCALARY
MERISTEM
ITS MAIN FUNCTION IS TO PROVIDE
ELONGATION AND GROWTH TO THAT
PART OF PLANT WHERE THEY ARE
PRESENT.
INTERCALARY OCCUR AT THE
BASE OF INTERNODES OR AT THE
BASE OF NODES OR LEAVES.

10. FUNCTIONS OF MERISTEMATIC
TISSUE
THE MERISTEMATIC TISSUE ACT AS A
PARENT TISSUE FROM WHICH OTHER
TISSUE DEVELOPS.
THE MERISTEMATIC TISSUE TAKES
PART IN GROWTH BY THE FORATION
OF NEW CELLS.
WITH THE HELP OF MERISTEMATIC
TISSUE PLANTS CONTINUE TO
PRODUCE NEW LEAVES, BRANCHES,
ROOTS , FLOWERS etc.

11. PERMANENT TISSUE
THE CELLS FORMED BY THE
MERISTEMATIC TISSUE TAKES UP THE
SPECIFIC ROLE AND LOSES ITS ABILITY
TO DIVIDE . THUS THEY FORM A TYPE
OF NEW TISSUE CALLED AS
PERMANENT TISSUE.
THE PROCESS BY WHICH THE
MERISTEMATIC TISSUE IS
TRANSFORMED INTO PERMANENT
TISSUE IS CALLED AS CELL
DIFFRENTIATION.
TYPES OF PERMANENT TISSUE:

12. SIMPLE PERMANENT TISSUE
THE SIMPLE PERMANENT TISSUE ARE
COMPOSED OF CELLS WHICH ARE
STRUCTURALLY AND FUNCTIONALLY
SIMILAR.
THE SIMPLE PERMANENT TISSUE HAS
ONE TYPE OF CELLS.
THE SIMPLE PERMANENT TISSUE IS
FURTHER CATEGORISED INTO
FOLLOWING TYPES:
a. PARENCHYMA
b. COLLENCHYMA

13. -
PARENCHYMA
THEY ARE LIVING AND HAVE A
POWER OF DIVISION.
FOUND IN BULK IN PLANT BODY.
THESE CELLS ARE ISODIAMETRIC (
EQUALLY EXPANDS ON ALL SIDES)
IT IS WIDELY DISTRIBUTED IN PLANT
BODIES SUCH AS STEMS , LEAVES ,
FLOWERS AND FRUITS.
THE PARENCHYMA TISSUE IS FOUND IN
THE SOFT PARTS OF THE PLANTS SUCH
AS ROOT CORTEX , GROUND TISSUE IN

14. FUNCTIONS OF PARENCHYMA
THE MAIN FUNCTION OF THE
PARENCHYMA IS TO STORE AND
ASSIMILATE FOOD . THUS IT ACT AS A
FOOD STORAGE TISSSUE.
IT SERVES AS A PACKING TISSUE .
IT TRANSPORTS MATERIAL.
THESE CELLS ARE METABOLICALLY ACTIVE
, THEIR INTERCELLULAR SPACES ALLOW
GASEOUS EXCHANGE.
IF THE CHLOROPLAST IS PRESENT IN THE
PARENCHYMA IT IS CALLED AS
CHLORENCHYMA AND IT PERDORMS
PHOTOSYNTHETIC FUNCTION.
IN HYDROPHYTES ,IT GIVES BUOYANCY TO

15. COLLENCHYMA
COLLENCHYMA ALSO CONSIST OF
LIVING CELLS.
THE CHRACTERISTIC FEATURE OF
THE COLLENCHYMA IS THE
DEPOSITION OF EXTRA CELLULOSE
AT THE CORNERS OF THE CELLS.
THERE IS NO INTERCELLULAR SPACES
BETWEEN CELLS AND THEY ARE
ELONGATED IN SHAPE.
FUNCTION OF COLLENCHYMA
IT PROVIDE MECHANICAL SUPPORT

16. SCLERENCHYMA
SCLERENCHYMA CELLS ARE DEAD AND
THEY ARE DEVOID OF THE PROTOPLASM.
THE CELL WALLS ARE LIGNIFIED.
DUE TO EXCESSIVE THICKENING OF
THE SCLERENCHYMA CELL WALL, THE
CELL CAVITY OR LUMEN IS ABSENT.
IN BETWEEN SCLERENCHYMA CELLS
THERE EXIST A MIDDLE LAMELLA
(CEMENTING MATERIAL)
FUNCTION
IT IS MECHANIC AND PROTECTIVE IN
FUNCTION.
IT PROVIDES ELASTICITY TO PLANT BODY

17. The three simple permanent tissue

18. COMPLEX PERMANENT TISSUE
THE COMPLEX PERMANENT TISSUE
CONSIST OF MORE THAN ONE TYPE OF
TISSUE HAVING A COMMON ORIGIN.
COMPLEX TISSUE TRANSPORT WATER ,
MINERAL , SALT AND FOOD MATERIAL TO
VARIOUS PARTS OF THE PLANT BODY.
 COMPLEX PERMANENT TISSUE CONSIST
OF :
a. XYLEM b. PHLOEM
XYLEM AND PHLOEM BOTH ARE
CONDUCTING TISSUE AND KNOWN AS
VASCULAR TISSUE. TOGETHER BOTH OF

19. XYLEM
XYLEM IS A CONDUCTING TISSUE .
XYLEM COMPOSED OF CELLS
OF FOUR DIFFERENT TYPES :
a. TRACHEIDS
b. VESSELS
c. XYLEM PARENCHY,MA
d. XYLEM SCLERENCHYMA
EXCEPT THE XYLEM PARENCHYMA, ALL
ELEMENTS ARE DEAD AND BOUNDED
BY THE THICK LIGNIFIED CELL

20. -
TRACHEIDS
 THESE ARE SINGLE CELLED.
THE ENDS REMAIN ENACTED.
THE WALS OF THE TRACHEIDS ARE VERY
THICK WITH NARROW LUMEN .
THEY CONDUCT WATER.
VESSELS
THESE WALLS OF THESE ARE MADE OF ROWS
OF CELLS.
THE END WALLS GET DISSOLVED AND
BECOME PERFORATED.
THE WALLS OF VESSEL ARE LESS THICK .
YHEY HAVE WIDER LUMEN.
XYLEM PARENCHYMA
IT STORES FOOD AND HELP IN LATERAL
CONDUCTION OF WATER

21. PHLOEM
THE PHLOEM CONDUCT ORGANIC
SOLUTE OR FOOD MATERIAL .
COMPONENTS OF PHLOEM ARE:
a. SIEVE TUBES
b. COMPANION CELLS
c. PHLOEM PARENCHYMA
d. PHLOEM FIBRES

22. -
SIEVE TUBES
THE SIEVE TUBES ARE SLENDER
TUBES LIKE STRUCTURE COMPOSED
OF ELONGATED THIN WALLED CELLS,
PLACED END TO END.
THEIR END WALLS ARE PERFORATED.
THE NUCLEUS IN EACH SIEVE CELL
DEGENRATE AT MATURITY. THUS NUCLEI
IS ABSENT IN MATURE CELL.
COMPANION CELL
THE COMPANION CELLS ARE THIN
WALLED CELLS AND CONTAIN VERY
ACTIVE CYTOPLASM WITH LARGE
ELONGATED NUCLEUS.

23. FUNCTION OF
PHLOEM
PHLOEM TRANSPORTS
PHOTOSYNTHETICALLY PREPARED
FOOD MATERIAL FROM LEAVES TO THE
STORAGE ORGAN AND LATER FROM
STORAGE ORGANS TO THE GROWING
REGIONS OF THE PLANT BODY.