2. • Unicellular organisms - Single cell
performs all basic functions. e.g. Amoeba

3. Multi-cellular organisms – Most of the cells
are specialize to carry our a few functions.
e. g. Human beings

4. In human
• Muscles – movement
• Nerve cells – carry messages
• Blood – transport – food, oxygen,
hormone, waste materials

5. • In multicellular organism - DIVISION OF
LABOUR

6. • TISSUE – A group of cells similar in
structure that work together to perform a
particular function.

7. PLANT TISSUE
• I) Meristematic tissue
• II) Permanent tissue

8. Meristematic tissue Permanent tissue
Cells devide repeatedly Cells are derived from
meristematic tissue &
normally do not devide
Undifferentiated Fully differentiate
Small Variable in shape and
size
Intercellular spaces
generally absent
Intercellular spaces are
present
Vacuole absent Large vacuoles in
mature cells

9. Name Location Function
Apical
meristems
Growing tips
(Apex) of roots
and stems
Elongation
Lateral
meristems
(Cambium)
Beneath the
bark, in vascular
bundles of dicot
stems
Increase in
diameter
Intercalary
meristems
Base of the
leaves /
internode
Increase of
length

11. Classification of Plant Tissues
Plant
Tissue
Meristmatic Permanent
Apical Lateral Intercalary Simple Complex
Parenchyma
Collenchyma
Sclerenchyma
Phloem
Xylem
Mature cells incapable of
cell division
Below bark,
Cambium, in
dicot roots
and stems
Internodes
of stem
Cells are capable of cell division
and have toipotency
Tips of
root and
stem

12. II) PARMANENT TISSUE
• i) Simple permanent tissue
• ii) Complex permanent tissue

13. Simple permanent tissue
Parenchyma Collenchyma Sclerenchyma
Location Soft parts of
plat – Cortex
of root,
ground
tissues in
stem,
mesophyll of
leaves
Below the
epidermis
of dicot
stem and
petiole
(Absent in
monocot)
In stem around
vascular bundle,
roots, veins of
leaves, hard
covering of seeds
and nuts

14. Nature • Cells are isodiametric
i.e. equally expanded on
all sides
• They may be oval,
round, polygonal or
elongated
• Nucleus is present and
hence living
• The cell walls are thin
and made of cellulose
Cytoplasm is dense with
a single large vacuole
Intercellular spaces may
be present
May contain
chlorophyll. Parenchyma
which contain
chlorophyll are called
chlorenchyma.
• The cells are
elongated and are
circular, oval or
polygonal in
cross-section
Cell wall is
unevenly
thickened with
cellulose at the
corners against
the intercellular
spaces
Nucleus is
present and hence
the tissue is living
• Vacuoles are
small
Intercellular
spaces are
generally absent
• If they contain
chlorophyll they
are known as
chlorenchyma
• The cells are long,
narrow, thick and
lignified, usually pointed
at both ends
• The cell wall is evenly
thickened with lignin and
sometimes is so thick that
the cell cavity or lumen
is absent
Nucleus is absent and
hence the tissue is made
up of dead cells
They have simple, often
oblique pits in the walls
• The middle lamella i.e.
the wall between
adjacent cells is
conspicuous

15. Function
Store and
assimilate food
Give mechanical
strength by
maintaining
turgidity
Prepare food if
chlorophyll is
present
Store waste
products like tanin,
gum, crystals and
resins
Provide mechanical
support to the stem
Allows easy bending
in various parts of the
plant without actually
breaking it
Gives mechanical
support to the
plant by giving
rigidity,
flexibility and
elasticity to the
plant body.