3. DEFINITION
A group or collection of similar cells
performing or help to perform same
function and arise from the same
origin are called tissues.
The tissues are of different types
depending on the functions of the
organism, they are mainly of two
categories PLANT TISSUES and
ANIMAL TISSUES.
4. PLANT TISSUES
Plants perform functions
which are different from
animals and also their structure
is different , hence they have
tissues which are different from
animals. They are further
classified into many sub
categories which is shown in
the table below:
5. Plant Tissues
Meristimatic Tissues
(These cells continuously divide throughout the life of the
plant)
Apical
Meristem
Lateral Meristem
Intercalary
Meristem
Permanent Tissues
(Cells with speciallised structure and function that have lost
their ability to divide further)
Simple Permanent Tissue
Parenchyma
Collenchyma
Sclerenchyma
Complex Permanent Tissue
Xylem
Phloem
6. MERISTEMATIC TISSUE
The main characteristic of this
tissue is that it is responsible for the
growth of plants.
The cells of this tissue continuously
divide and later differentiate ( i.e.
get converted ) into permanent
tissue.
7. CHARACTERISTICS OF THE TISSUE
The cells are made of thin & elastic
cell wall made of cellulose.
The cells may be round , oval,
polygonal or rectangular in shape.
They are compact, having no
intercellular space.
There is a large nucleus and abundant
cytoplasm.
The protoplasm contains very few or no
vacuoles at all.
8. THIS TISSUE OCCURS AT SPECIFIC
REGIONS OF THE PLANT BODY
This is so because in plant
body growth occurs only at
these regions.
Hence , on the basis of this
there are 3 types of
meristem :
1. APICAL MERISTEM
2. INTERCALARY
MERISTEM
3. LATERAL MERISTEM
9. APICAL MERISTEM
As the name
suggests this tissue is
present at the apex
of the main & lateral
shoots and roots.
This tissue gives the
plant body a linear
growth.
10. LATERAL MERISTEM
This tissue lies on
the sides of the
plant body.
It lies under the
bark of the plant in
form of cork
cambium.
It gives the plant
it’s width or girth.
11. INTERCALARY MERISTEM
This tissue is present
at the base of the
nodes, internodes,
leaves etc.
They are also present
in between the
permanent tissue.
They give the plant
growth in length.
12. PERMANENT TTISSUE
These tissues arise from the meristematic
tissue.
The cells of this tissue gradually loose their
power to divide and acquire a definite
shape, size and function.
These tissues may be living or dead.
There are 2 types of permanent tissues
1. Simple permanent tissue
2. Complex permanent tissue.
13. SIMPLE PERMANENT TISSUE
This tissue comprises of same
type of cells which perform the
same function and all arise from
the same origin. There are three
categories of simple permanent
tissues: Parenchyma,
Collenchyma, & Sclerenchyma.
15. PARENCHYMA
Characteristics:
a) The cells are living.
b) The cells are thin walled.
c) There may or may not be
intercellular spaces.
d) They are the most
unspecialized cells.
e) No depositions are seen, the
cell wall consists only of
cellulose.
f) There is a prominent
nucleus, cytoplasm &
vacuoles.
16. There are some special types of
parenchyma tissues :
Storage parenchyma : The cells enlarge to store
nutrients & water.
Aerenchyma : Air cavities are present in the
parenchyma tissue to provide buoyancy to the
aquatic plants.
Chlorenchyma : These parenchyma cells have
presence of chlorophyll & hence can perform the
function of photosynthesis.
Parenchyma tissue is found generally in all parts of
the plant body. It forms the Ground tissue in leaves,
stem, roots & fruits etc.
17. FUNCTIONS OF PARENCHYMA
a) To store materials such as starch, proteins,
hormones etc. And waste products such as gum,
tannin, resin etc.
b) Parenchyma cells perform the metabolic activities
of the plant.
c) Forms the packaging tissue between the
specialized tissue.
d) By providing turgidity , they provide mechanical
strength.
e) Chlorenchyma helps in performing photosynthesis.
19. Characteristics:
a) It has cells which are
somewhat elongated.
b) The cell walls are thin
except at the angular region
( where the cells join). The
thickenings are caused due
to deposition of cellulose or
pectin.
c) There is o or less
intercellular space.
d) The cells are living, have
distinct nucleus & dense
protoplasm.
e) They often contain
chlorophyll.
Functions :
a) Providing mechanical
strength is the primary
function.
b) Provide flexibility.
c) Photosynthesis, as they
contain chlorophyll.
They are present below
the epidermis in dicot
stems and leaves.
They absent in dicot
roots and all parts of
monocot plants.
CHARACTERISTICS AND
FUNCTIONS
22. EPITHELIAL TISSUES
This tissue forms outer living of the
body. It protects interval organ from
external environment.
It is of four types:
Squamous.
Cubic.
Ciliated columnar.
Glandular.
23. SQUAMOUS EPITHELIUM
It is made up of
thin, flat irregular
Shaped cells .
It also forms a
selectively
permeable surface through which
filtration occurs .
24. CUBIC EPITHELIUM
It consists of cube like
cell which are square
in section but the free
surface appear hexagonal.
It is found in kindly tubules, thyroid,
vesicles and in glands.
25. CILIATED COLUMNAR
This epithelial is
formed by in the
sperm ducts.
The rhythmic,
concentrated beating of the cilia
moves solid particles in one
direction through the ducts.
26. MUSCULAR TISSUES
This tissue is that which is
responsible in our body.
This tissue is divided in three
types:
Striated muscle.
Smooth muscle.
Cardiac muscle.
27. STRIATED MUSCLE
The cells of this muscle have
many nucleus.
These muscle show alternate
light &dark bands.
These help in body movement.
These are present in our limbs.
28. SMOOTH MUSCLE
These have long cells which
have single nucleus.
The cells of this muscle is spindle
in shape.
They are also called unstraited
because we can not control them
29. CARDIAC MUSCLE
It is the muscle which is
present in heart.
These muscle are also called
involuntary muscle.
These muscle have cylindrical
&branched muscle.
30. CONNECTIVE TISSUES
It serves as storage Sid of
calcium & phosphate.
Bone provides shape &
skeleton support to the body.
Cartilage provides support &
flexibility.
31. NERVOUS TISSUE
A Tissue which is specialized to
transmit messages in our body is
nervous transmit. Brain, spinal
cord and nerves are all composed
of nervous tissues. Nervous
tissues contains highly
specialized unit cells called nerve
cells or neurons.
