Tissue classification and their type and functions

1. TISSUE
BY,
BABITA DODKE
NAGPUR COLLEGE OF PHARMACY

2. TISSUES
A tissue is a group of similar cells and their surrounding material that work
together to perform a specific function. Tissues represent the level of
biological organization between individual cells and complete organs.
The study of tissues is known as histology

5. TISSUES
Epithelial
tissue
Connective
tissue
Muscular
tissue
Nervous
tissue
A.Simple
epithelium
i. Squamous
ii. Cuboidal
iii. Columnar
iv. Pseudostratifie
d
B.
Stratified
epithelium
i.
Transitional
ii.Stratified
squamous
non-
keratinized
iii.
Stratified
Cells
a. i.
Fibroblasts
ii. Fibrocytes
b. Adipose /fat
cells
c. Plasma cells
d. Mast cells
e. Macrophages
f. Leucocytes
g. Pigment cells
h.
Mesenchymal
cells
Fibres
i. Collagen
fibres
ii. Elastic fibres
iii. Reticular
fibres
i. Skeleta
l
muscl
e s
ii. Smoot
h
muscl
e s
iii. Cardia
c
muscle
s
iii.
i.
Central
nervou
s
system
ii. Peripher
al
nervous
system
Autonomi
c nervous
system

6. EPITHELIAL TISSUE
Epithelial tissues are widespread throughout the
body. They form the covering of
all body surfaces, line body cavities and hollow
organs, and are the major tissue in glands.
Function:
i. Protection
ii. Secretion
iii. Absorption
iv. Forms glands & ducts
Epithelium can be simple or stratified.

7. A. Simple Epithelium
An epithelium is called as simple when all the cells rest on
the
basement membrane. It can be :
i. Squamous epithelium- is one in which cells areflattened
with nuclei raising a bulge in the cell. It allows
rapid exchange of substances through it. e.g. epithelial
lining of alveloi .

8. ii. Cuboidal epithelium - is one in which
cells are like a square where height of
the cell is equal to the width of the cell.
The nucleus is central and round. Its
main function is absorption and
secretion e.g. epithelial lining of follicles of
thyroid gland.

9. iii. Columnar epithelium- is the one wherein
the height of the cells is greater than the
width of the cells. The nuclei is basal
and vertically elongated.
• Functions of a columnar cell are protection,
secretion and absorption. e.g. epithelial lining
of fallopian tubes.
Cilia
Single layer of
column
of rectangular cells
Basement
membran
e

10. Pseudo stratified
Pseudo = false, stratified= multilayered. As the
name suggest
there is false appearance that the epithelium is
multilayered. In fact some cells are short while
the others are tall but all the cells rest on
basement membrane e.g. epithelial lining of
trachea.

11. B. STRATIFIED EPITHELIUM
Multilayered epithelium is known
as stratified epithelium.
i. Transitional epithelium- this kind
of epithelium lines an organ
which is distensible e.g. urinary
bladder.

12. ii. Stratified squamous non- keratinized epithelium–
it is a multilayered epithelium in which
basal cells are columnar. E.g. epithelial
lining of esophagus.

13. iii. Stratified squamous keratinized
epithelium – It is a multilayered epithelium
just
like Stratified
squamous
non-
keratinized
epithelium but here the top most layer is
that of keratin through which water can
neither be evaporated from the body as in
standing in sun nor can it be absorbed into
the body as while swimming e.g. epidermis
of skin.

14. CONNECTIVE TISSUE
As the name suggests it connects different
components
of our body. It is made up of cells,
fibres
Fibroblasts, fibrocytes, macrophages and
and matrix.
adipose cells
are the example of some connective tissue cells. Matrix
is composed of ground substance and fibres.
Functions:
i. Providing support to different parts of our
body.
ii. Connects different components of our
body.
iii.
It is a medium for exchange
of nutrients, metabolites and oxygen between
blood
and cells.

15. CELLS
i. Fibroblasts- the cells which synthesize
collagen fibres, elastic fibres and lays
down matrix are know as
fibroblasts.
ii.Fibrocytes- when the fibroblasts
mature they are known as fibrocytes.

16. b. Adipose / fat cells- they are rounded cells but they
are usually present in group, they get mutually
compressed so may have variable shape. They have fat
globule in their cytoplasm which pushes the nucleus to
periphery giving the cell signet ring appearance. Their
function is to store fat in their cytoplasm.
c. Plasma cells- rounded to ovoid basophilic
cells
wit
h
cart wheel nucleus. They are rich in rER. Their function
is to synthesize immunoglobulins.

17. FAT CELLS
PLASMA CELLS
CART
WHEEL
NUCLEUS
PLASM
A
CELLS

18. d.Mast cells- they are involved in inflammatory
reactions.
e.Macrophages- their function is to engulf various
foreign
particles.
f.Leucocytes- White Blood Cells are known as
leucocytes. They are neutrophils, lymphocytes, eosinophils,
basophils and monocytes. They have defensive action.
g.Pigment cells- import brown color to the skin when they
are present in epidermis. Their presence offers protection
against ultraviolet rays of the sunlight.
h.Mesenchymal cells- are undifferentiated cells. They
can
differentiate into a variety of cell types.

20. FIBRES
a. Collagen fibres- they are flexible but offer great
tensile strength. They found in tendons,
ligaments and all kinds connective tissues.
b. Elastic fibres- they can stretch and then come back
to force is relieved.
They ligamentum flava
and in
their normal size when
stretching are found in
ligamentum nuchae, the wall of
large arteries.
c. Reticular fibres- they are special type of collagen
fibres and can be seen only by special stain. They are
seen in the connective tissue framework of spleen,
liver lymph nodes.

22. Connective tissue can
be :
A. General connective tissue:
a. Loose connective tissue
b. Dense connective tissue
c. Mucoid tissue
d. Adipose tissue
B. Specialized connective tissue:
this comprises of bones, cartilages an hemolymphoid
tissue.
a. Cartilage – Hyaline cartilage, elastic
cartilage, fibrocartilage
b. Bone- made up of organic & inorganic
substances.
c. Hemolymphoid tissue- blood & lymphatics

23. 5
Supports and
cushions joints
Mucoid Tissue
Cartilage
Found in embryonic
development 3
4
Provides flexibility
and support
Stores energy and
insulates
Connective
Tissues 6 Provides structural
support
Dense
Connective
Tissue 2
Adipose Tissue
Connective Tissues in Animals
Offers strength and
rigidity 7 Hemolymphoid
Tissue
1
Loose
Connective
Tissue
Involved in immune
functions
Bone

24. MUSCULAR TISSUE
There are three types of muscles namely-
a. Skeletal muscle- they help in locomotion
e.g. biceps femoris.
b. Smooth muscles- they are present in
the viscera of our body e.g. muscle in the
wall of stomach.
c. Cardiac muscle- it is seen only in the
heart. Contraction of this muscle helps in
pumping of blood throughout our body.

25. Skeletal Muscle
Heart Locomotion
Blood Pumping
Muscles Biceps Femoris
Cardiac Muscle
Smooth Muscle
Types of Muscles and Their Functions
Stomach Wall
Viscera

27. NERVOUS TISSUE
Nervous tissue is the primary component of the nervous system,
responsible for coordinating and controlling many body
activities. It is found in the brain, spinal cord, and nerves
that branch throughout the body. Unlike other tissues, nervous
tissue is specialized for rapid communication through electrical
and chemical signals.

28. A. Neurons (Nerve Cells)
Neurons are the functional units of the nervous system.
They are specialized to receive, process, and transmit
information.
Cell Body (Soma): The metabolic center containing the
nucleus and organelles.
Dendrites: Short, branched extensions that receive signals
from other neurons.
Axon: A long, slender projection that carries electrical
impulses (action potentials) away from the cell body toward
a target (another neuron, muscle, or gland).
1. Cellular Composition
Nervous tissue consists of two major classes of cells: neurons and
neuroglia.

29. B. Neuroglia (Glial Cells)
Glial cells are "helper" cells. They do not conduct
impulses but are essential for the survival and function
of neurons.
In the Central Nervous System (CNS): *
Astrocytes: Support and regulate the chemical
environment.
Oligodendrocytes: Create the myelin sheath (insulation) in
the brain and spine.
Microglia: Act as the immune defence, clearing debris.
Ependymal cells: Line cavities and produce cerebrospinal

30. Feature Neurons Neuroglia
Primary Role Signal transmission
Support and
protection
Ability to Divide
Generally cannot
(amitotic)
Can divide (mitotic)
Size
Large, with long
processes
Much smaller
Abundance Fewer
5 to 10 times more
numerous
In the Peripheral Nervous System (PNS):
•Schwann cells: Form the myelin sheath around peripheral
nerves.
•Satellite cells: Provide structural and nutritional support.

31. CONCLUSION
Tissues are communities of cells that have functions beyond
what any single cell type could accomplish.
Healthy tissues require the proper mix of cells, and the cells
within them must be oriented correctly and dividing at an
appropriate rate.

32. Thank You