The document provides a comprehensive overview of the organization of the human body at the tissue level, detailing the four main types of tissues: epithelial, connective, muscular, and nervous. Each tissue type is further classified, describing their structure, location, and functions within the body. The document highlights the specific characteristics and roles of various subtypes of tissues, emphasizing their importance in maintaining the body's integrity and function.

1. ORGANISATION OF THE
HUMAN BODY AT THE
TISSUE LEVEL
BY - MUSKAN KAPOOR

2. INTRODUCTION
● Tissue is a collection of cells which have similar structure and
perform relatively common function.
● There are 4 types of tissues that are:-
- Epithelial tissues
- Connective tissues
- Muscular tissues
- Nervous tissues

3. EPITHELIAL
TISSUES
● In this cell are closely packed without any
intracellular spaces.
● Location :- from the outer and inner lining
of most of the organs such as
gastrointestinal tract(GIT), urinary tract,
blood vessels, heart chambers etc.
- Found on the entire exposed surface of the
body such as skin.
● Functions :- play important role of defence
and protect body organs.
- Show different function in different organs
such as :- secrete gastric juice in stomach,
absorb digested food in intestine, remove
waste as sweat in skin.
● Types :- simple epithelial tissues
- Compound epithelial tissues

4. SIMPLE EPITHELIAL TISSUES
● It line the inner side of passageways, hollow organs and body cavities.
● They are characteristic of regions where secretion or absorption occurs.
● Types :- simple squamous epithelium
- Simple Cuboidal epithelium
- Simple columnar epithelium

5. ● Simple squamous epithelium :- they are extremely thin and flat.
- The width of such cells is much greater than the height.
- They are found in areas where exchange takes place.
- Site :- lung alveoli, bowman’s capsule in kidney, blood vessels.
● Simple cuboidal epithelium :- they are cube shaped and on surface
views cell look either polygonal or hexagonal.
- They provide limited protection to an organ.
- Sites :- pancreas, salivary glands, kidney tubules, duct that transport
exocrine secretion.

6. ● Simple columnar epithelium :- they are tall, slender and rectangular in shape and are
placed in shape and are placed side by side like columns.
- They occur in regions where absorption or secretion occurs.
- Sites :- most of GIT lining and excretory glands.
- Types :- ciliated columnar epithelium : it consist of modified columnar cells.
: it has motile hair like projection called cilia which push the
substances in a definite direction
: site - oviducts and renal tubules.
- Pseudostratified columnar epithelium :- pseudo means false and stratified means
multilayered.
:it consist of columnar cells of unequal heights.
: sites - trachea lining and parts of male reproductive tract.

7. COMPOUND EPITHELIAL TISSUES
● Also known as stratified epithelial tissues.
● They are usually found in areas subject to mechanical and
chemical stresses.
● Types :- stratified squamous epithelium
- Stratified transitional epithelium
- Stratified columnar epithelium

8. ● Stratified squamous epithelium :- the deeper layers of this tissue divide themselves
to form daughter cells which move towards the surface.
- During this movement these cells become more and more flattened.
- They die and dry out.
- It is present on surfaces which are not subjected to friction
- Sites : outer skin , glans of penis, mucous membrane in mouth and vagina
● Stratified transitional epithelium :- it consist of rounded cells which are very elastic
and have capacity of dividing themselves.
- They lines the organ that are distensible.
- Sites: lining of urinary bladder, ureter
● Stratified columnar epithelium :- it provide
protection along portion of respiratory tract,
GIT and reproductive tract.

9. CONNECTIVE TISSUE
● It connect one tissue or organ with other tissues or organs.
● They are made up of cells which are found individually or in groups of two or more.
● Space between the cells is called matrix which is filled with different substances.
● Functions :- provide support and protect internal delicate organ of the body as bone
and cartilage do.
- Transport material from one part of the body to other as blood does.
- Store energy sources such as fats, in large quantities.
- Defend body from invasion by microorganisms.
● Types :- connective tissue proper
- Supporting connective tissue or skeleton tissue
- Fluid connective tissue

11. CONNECTIVE TISSUE PROPER
● Connective tissue fibres :- it is of 3 types - collagen fibres
- Elastic fibres
- Reticular fibres
➔ Collagen fibres :- they are strong and almost inflexible.
- They consist of protein collagen and are arranged in
bundles.
➔ Elastic fibres :- they are flexible and branched fibres
which consist of protein elastin.
- Site - in walls of arteries and lining of nerve cells.
➔ Reticular fibres :- they are much thinner than other two types of fibres.
- The substance reticulin forms very finely branched out fibres which cannot be
stretched.
- Site - spleen and liver

12. CONNECTIVE TISSUE PROPER
● It is of 2 types :- loose connective tissue
- Dense connective tissue
● LOOSE CONNECTIVE TISSUE :- it is of 3 types - areolar tissue
- Adipose tissue
- Reticular tissue
➔ AREOLAR TISSUE -it contain all 3 fibres types
- Site : beneath epithelium of skin, GIT, respiratory and urinary tract.
➔ ADIPOSE TISSUE - It is made up of rounded cells filled with fat globule in their cytoplasm
- Site : fat cells, deeper layer of skin, buttocks, breast.
- Function : serve as reserve store of fuel
: act as heat insulator
➔ Reticular tissue : it is basic framework for many organs that have complex tissue
- Site : liver, spleen , lymph nodes
- Function: provide supporting framework

13. DEEP
CONNECTIVE
TISSUE
● It is occupied by densely packed collagen
fibres.
● Example - tendons, ligaments and fasciae.
● Tendons :- they are mainly white tightly
packed fibres of protein collagen that run
parallel to form cord like structures.
- They are strong, flexible and resistant to
pull
- They connect muscles with bones and
facilitate in movement of limbs.
● Ligaments :- they are primarily made up of
densely packed yellow fibres of protein
elastin that run parallel to form cord like
structures.
- They can tolerate a moderate amount of
stretching.

14. ● Fasciae :- they are sheets of connective tissues which contain
collagen fibres.
- It surround organs such as skeletal muscles, attach skeletal
muscles to bone and distribute the forces of muscular
contraction over a large area.

15. SUPPORTING TISSUE PROPER
● It provide strong framework that support and give definite shape to the body.
● They also protect internal delicate organ of the body.
● Example :- cartilage and bone
● Cartilage - it is relatively soft and flexible
- They are surrounded by smooth and clear walls called lacunae.
- Surface of cartilage is formed by tough connective tissues fibres i.e. perichondrium.
- Functions - it reduces friction between bony surfaces .
- It provide stiff but somewhat flexible support to body surfaces.
● Bone - they are relatively harder and stronger than cartilage because matrix consist of
yellow elastic fibres combine with phosphate and carbonates of calcium and magnesium
salts.
- All long bones of the body have a yellow central cavity which is filled with cells called bone
marrow.

17. FLUID CONNECTIVE TISSUES
● It has a large number of different types of cells suspended in a fluid ground
substance.
● Types :- blood, lymph
● Blood - the matrix in blood is a fluid and blood cells.
- The plasma contains large number of blood cells with widely different functions.
● Lymph - it is the plasma after it has come out from capillaries .
- It give nourishment to the tissues and removes waste product from them.
- It is drained off by tiny lymphatic vessels which join to form large lymph vessels
and finally open into the right atrium .

18. MUSCULAR TISSUE
● It is specialised for contraction .
● It is of 3 types :- skeletal muscle
- Cardiac muscle
- Smooth muscle
● Skeletal muscle :- they are generally attached to bones at both ends by means of tendon,
hence contraction produces movement of the skeleton.
- The tongue, superior portion of oesophagus, and sphincter and diaphragm are also
connected to skeletal muscle but they don’t cause movement of skeleton.
- Each muscle fibre is made up of many fibrils called myofibrils, they lie parallel to each
other and are striated.
- In between successive myofibrils there is a thin layer of cytoplasm called sacroplasm .

19. ● Cardiac muscle - it is striated.
- It is found only in the heart where the myocardial cells are short, branched and
intimately interconnected to form a continuous fabric .
- The intercalated disc couple myocardial cells together mechanically and electrically.
- It is an involuntary muscle, it is referred to as striated involuntary muscle.
● Smooth muscle - it is small and spindle shaped with a single nucleus located centrally.
- Actin and myosin filaments are scattered throughout the cytoplasm and there are no
cross striations.
- Sites : wall of blood vessels, around hollow organs such as urinary bladder, in layers
around respiratory , circulatory and reproductive tract.
- Smooth muscle fibres contract on their own.

20. NERVOUS TISSUE
● It is specialised for conduction of electrical impulses from one region of
body to another.
● It contains 2 type of cells: conducting cells or neuron cells and
supporting cells or glial cells.

21. ● Neuron : - it is structural and functional unit of
the nervous system.
- It consist of cell body or nerve cell with several
cytoplasmic extensions.
- It has 5-7 short processes called dendrites,
they transmit impulses towards the cell body.
- A single long process is called axon, it conveys
impulses away from the cell body.
- In addition it contains Nissl’s granules i.e.
membrane bound cavities which consist of
ribonucleoproteins.
- Neurons are specially designed to receive
stimuli from the environment.
- The axon is coated with a thick layer called
myelin sheath.
- Myelin facilitates conduction of nerve impulse,
it confines the nerve impulse to individual

22. ● Neuroglia - also known as glial
cell.
- It support the nerve cells.
- There are about ten times as
many glial cells as neurons.
- Functions - isolate and protect
the cell membrane of neurons.
- Provide a supporting framework
for neural tissue .
- Regulate the composition of
intestinal fluid.
- Act as phagocytes that defend
neural tissue from pathogens

23. THANK YOU