ZOOLOGY
PRE-MEDICAL
NURTURE COURSE
Study Material
Structural organisation in
Animals (Animal Tissues)
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
Structural Organisation in Animals (Animal Tissue)
Marie François Xavier Bichat (14 November 1771 - 22 July 1802)was a French
anatomist and physiologist who is best remembered as the father of modern
histology and descriptive anatomy. Despite working without a microscope, he
was the first to introduce the notion of tissues as distinct entities, and
maintained that diseases attacked tissues rather than whole organs or the
N
entire body, causing a revolution in anatomical pathology.Bichat was born at
Thoirette in Jura, France. His father was Jean-Baptise Bichat, a physician who
had trained at Montpellier and was Bichat's first instructor. His mother was Jeanne-Rose Bichat, his
father's wife and cousin. He entered the college of Nantua, and later studied at Lyon. He made rapid
LL
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progress in mathematics and the physical sciences, but ultimately devoted himself to the study of
anatomy and surgery under the guidance of Marc-Antoine Petit (1766-1811), chief surgeon to the
Hotel-Dieu at Lyon. The revolutionary disturbances compelled him to flee from Lyon and take refuge
in Paris in 1793. There he became a pupil of P. J. Desault, who was so impressed with his genius that
he took him into his house and treated him as his adopted son. For two years he took active part in
Desault's work, at the same time pursuing his own research in anatomy and physiology. Desault
passed in 1795. At age 29 he was appointed as the chief physician to the Hotel-Dieu. In 1796, he and
several other colleagues formally founded the Societe d'Emulation de Paris, which provided an
intellectual platform for debating problems in medicine. He died at age 30, fourteen days after falling
A
down a set of stairs at Hotel-Dieu and acquiring a fever. He is buried at Pere Lachaise Cemetery.
68
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Pre-Medical : Biology

STRUCTURAL ORGANISATION IN ANIMALS
(ANIMAL TISSUES)

01. INTRODUCTION
N
In unicellular organisms, all functions like digestion,
respiration and reproduction are performed by a single
cell. In the complex body of multicellular animals the
same basic functions are carried out by different
groups of cells in a well organised manner. The body of
a simple organism like Hydra is made of different types
of cells and the number of cells in each type can be in
thousands. The human body is composed of billions of
cells to perform various functions. How do these cells
in the body work together? In multicellular animals, a
group of similar cells along with intercellular
substances perform a specific function. Such an
organisation is called tissue.
You may be surprised to know that all complex animals consist of only four basic types of
tissues. These tissues are organised in specific proportion and pattern to form an organ like
stomach, lung, heart and kidney. When two or more organs perform a common function by
their physical and/or chemical interaction, they together form organ system, e.g., digestive
system, respiratory system, etc. Cells, tissues, organs and organ systems split up the work in a
way that exhibits division of labour and contribute to the survival of the body as a whole.
Introduction
Organ and organ system
Epithelial tissues
Cell Junctions
Glands
Connective tissues
Cartilage
Bone
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







Complex body
Organ system
Organs
Tissues
Cells
A
02. ORGAN AND ORGAN SYSTEM
The basic tissues mentioned above organise to form organs which in turn associate to form
organ systems in the multicellular organisms. Such an organisation is essential for more efficient
and better coordinated activities of millions of cells constituting an organism. Each organ in our
body is made of one or more type of tissues. For example, our heart consists of all the four
types of tissues, i.e., epithelial, connective, muscular and neural. We also notice, after some
careful study that the complexity in organ and organ systems displays certain discernible trend.
This discernible trend is called evolutionary trend (You will study the details in class XII). You are
being introduced to morphology and anatomy of three organisms at different evolutionary
levels to show their organisation and functioning. Morphology refers to study of form or
externally visible features. In the case of plants or microbes, the term morphology precisely
means only this. In case of animals this refers to the external appearance of the organs or parts
of the body. The word anatomy conventionally is used for the study of morphology of internal
organs in the animals. You will learn the morphology and anatomy of earthworm, cockroach
and frog representing invertebrates and vertebrates.
69

Structural Organisation in Animals (Animal Tissue)
®
ANIMAL TISSUES

structure of the cells vary according to their function. Therefore, the tissues are different
 The
and are broadly classified into four types : (i) Epithelial, (ii) Connective, (iii) Muscular and
(iv) Neural.
Epithelial tissue
Connective tissue
Muscular tissue
Neural tissue
Covering and
protective
tissue
To connect structures
To provide support the body.
To transport substances in the
body.
Perform contraction
and relaxation which
helps in movement
and locomotion.
To generate
and conduct
impulses in
body.
03. EPITHELIAL TISSUE
(1) PROPERTIES OF EPITHELIAL TISSUES
Word epithelium is composed of two words.
Epi – Upon
Thelia – Growth
N

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A tissue which grows upon another tissue is called Epithelium.
Basement
membrane
It always rest upon underlaying connective tissue. Epithelial cells are compactly packed
with little inter cellular matrix.
A

Connective tissue





70
Due to less intercellular spaces blood vessels, lymph vessels and capillaries are unable to
pierce this tissue so blood circulation is absent in epithelium. Hence cells depend for their
nutrients on underlying connective tissue.
Power of regeneration is high in this tissue.
Between epithelium and connective tissue, a thin non living non-cellular basement
membrane is present which is highly permeable.
Basement membrane is secreted by both epithelium and connective tissue and made up
of glycoproteins, mucopolysaccharides and protein fibres.
This tissue has a free surface, which faces either a body fluid or the outside environment
and thus provides a covering or a lining for some part of the body.
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Pre-Medical : Biology

All cells in epithelium are held together with little intercellular material. In nearly all animal

(2) CELL JUNCTIONS
tissues, specialised junctions provide both structural and functional links between its individual
cells.
Cell junctions are found in epithelium and other tissues.
(A) Tight Junctions help to stop substances from leaking across a tissue.
(B) Adhering junctions perform cementing to keep neighbouring cells together.
(C)
Gap junctions facilitate the cells to communicate with each other by connecting the
molecules.
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Desmosomes
(Macula
Adherens)
N
cytoplasm of adjoining cells, for rapid transfer of ions, small molecules and sometimes big
Tonofibril
Tight-Junction
Gap Junction
BASEMENT MEMBRANE
A
(3) Modifications of Plasma membrane
(1) Microvilli


(2) Cilia/Kinocilia
(i) Minute process
(i) Long cylindrical process
(same diameter from base to apex)
(ii) Non motile
(ii) Motile
(iii) Function –
Increase surface area for
Absorption & secretion.
(iii) Function :Helps in movement & Locomotion.
It is the only tissue which originated from all the three primordial germinal layers.
Power of regeneration is absent or least in nervous tissue.
71

®
 BEGINNER’S BOX

1.
Structural Organisation in Animals (Animal Tissue)
INTRODUCTION & EPITHELIAL TISSUE
Gap junctions :(1) help to stop substances from leaking across a tissue.
(2) perform cementing to keep neighbouring cells together
(3) provide stretchability to the epithelium
(4) facilitate the cells to communicate with each other by connecting the cytoplasm of
adjoining cells.
2.
Basement membrane of epithelium tissue is composed of :(1) Lipoprotein
(3) Mucopolysaccharide and chromoprotein
(4) Mucopolysaccharide and glycoprotein
3.
Epithelial tissue form :(3) Nerve cells
4.
(2) Muscles
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(1) Protective covering
N
(2) Polypeptide
(4) Corpuscles.
Basement membrane is formed of :(1) Epidermal cells
(2) Endodermal cells
(3) Both 1 and 2
(4) None of the above but present below epithelial cells.
A
(4) TYPES OF EPITHELIUM TISSUE
(A) Simple epithelium
(B) Compound epithelium (Stratified)
– Composed of single layer of cells
– Consists of 2 or more cell layers
– It has protective function as it does in our skin
– Functions as lining for body cavities,
Ducts and tubes
On the basis of shape /
structural modifications
(ii) Nonstretchable
of cells
(i) Stretchable
(Transitional)
(i) Simple Squamous
(ii) Simple Cuboidal
(iii) Simple Columnar
(iv) Pseudostratified
72
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Pre-Medical : Biology

Simple Squamous Epithelium :

The squamous epithelium is made up of compactly packed single thin layer of flattened
(A) Simple Epithelium :
(i)

cells with irregular boundaries. They are found in the walls of blood vessels and air sacs of
lungs and are involved in a functions like forming a diffusion boundary.
Flattened cell
Simple epithelium: Squamous
Old NCERT XI Page No. 101, Figure No. 7.1 (a)
This epithelium is associated with filtration & diffusion.
N

e.g. :Bowman's capsule
–
Alveoli of lungs (air sacs of lungs)
–
Inner lining of blood vessels
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(ii)
–
Simple Cuboidal Epithelium :
The cuboidal epithelium is composed of a single layer of cube-like cells.
Cell membrane
Nucleus
Cytoplasm
Basement membrane
A
(Simple cuboidal epithelium)
Cube-like cell
Simple epithelium Cuboidal
Old NCERT XI Page No. 101, Figure No.7.1 (b)

This epithelium helps in absorption, secretion.

It is commonly found in ducts of glands and tubular parts of nephrons of kidneys.
73

Structural Organisation in Animals (Animal Tissue)
®
Modifications of simple cuboidal epithelium

(a) When microvilli are present on free end of cuboidal cells then it is called as

Brush bordered cuboidal epithelium.

Found in PCT of nephron.
Microvilli
Cuboidal cell
Nucleus
Basement membrane
(b)
When cilia present on free end of cuboidal cells then it is called as ciliated cuboidal
epithelium.

Found in collecting duct.
N
Cilia
Cuboidal cell
Nucleus
Basement membrane
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(iii) Simple Columnar Epithelium :
(a) The columnar epithelium is composed of a single layer of tall and slender cells. Their
nuclei are located at the base. They are mainly present in the inner surface of hollow
organs like bronchioles and fallopian tubes.
(b) Function :- Help in secretion and absorption.
Tall cell
Simple columnar epithelium
Old NCERT XI Page No.101, Figure No. 7.1 (c)
(c)
A

Modifications of Simple Columnar epithelium
Brush Bordered Columnar epithelium :
When microvilli are present on free end of columnar epithelium.
e.g. Gall bladder (helps in concentrating bile juice)
microvilli
Basement
membrane
Connective
tissue
74
Nucleus

Pre-Medical : Biology



®
Ciliated columnar epithelium :
Their function is to move particles or mucus in a specific direction over the
epithelium.
eg.
Fallopian tube
eg.
Bronchioles
→
Conduction of gametes
Cilia
Columnar cell
Nucleus
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Tall cell
N
Basement membrane
Simple epithelium Columnar cells bearing cilia
Old NCERT XI Page No. 101, Figure No. 7.1 (d)

Glandular columnar epithelium :
Unicellular mucous secreting
goblet cells are also present
in between columnar cells.
Stomach
A
eg.
Glandular surface
Columnar cell
Nucleus
Basement membrane
Large intestine

Glandular Brush-bordered columnar epithelium :
When microvilli present on free end of columnar cells and in between these cells
goblet cells are also present.
eg.
Small intestine
Glandular surface
Microvilli
Columnar cells
Nucleus
Basement membrane
75

Structural Organisation in Animals (Animal Tissue)
®
 (iv) Pseudostratified Epithelium :

It is also a modification of columnar epithelium that contains long & short cells.
  Nucleus in both cells are present on different level so it appears bilayered because few
cells are too short to reach the top surface but all cells are present on single basement
membrane, so it is unilayered.
MODIFICATION :
Pseudostratified ciliated columnar glandular epithelium (PSCCGE) :
In this epithelium, cilia are present on free surface of long cells and goblet cells are also
present in this epithelium.

Respiratory epithelium of nasal chambers

Trachea

Bronchi
N
eg.
Goblet cell
Cilia
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Tall cell
Short cell
Basement
membrane
Connective
tissue
Pseudostratified Ciliated Columnar Glandular Epithelium { PSCCGE }
BEGINNER’S BOX
Pseudostratified epithelium is present in :(1) Nephron & Neuron
(2) Larynx & Pharynx
(3) Trachea & Bronchi
(4) Urinary Bladder & Intestine
A
1.
TYPES OF EPITHELIAL TISSUE
2.
Columnar epithelium with microvilli or brush border is present in :(1) Gall Bladder
(2) Stomach (3) Appendix
(4) Pharynx
3.
Epithelial tissue originated from :(1) Ectoderm
(2) Endoderm (3) Mesoderm
(4) All of above
4.
Inner lining of intestine, stomach & liver is made up of :(1) Simple squamous
(2) Simple cuboidal
(3) Simple columnar
(4) Pseudo stratified epithelium.
5.
Nucleus of a epithelium found in stomach is located at ___________ of cell.
(1) Apex
(2) Middle
(3) Base
(4) Nucleus is absent
76
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Pre-Medical : Biology


(B) Compound epithelium :
Compound epithelium is made up of
more than one layer (multi-layered) of
cells and thus has a limited role in
secretion and absorption (Figure). Their
main function is to provide protection
against chemical and mechanical
stresses. They cover the dry surface of
the skin, the moist surface of buccal
cavity, pharynx, inner lining of ducts of
salivary glands and of pancreatic ducts.
®
Multilayered
cells
Old NCERT XI Page No. 102, Figure No. 7.3
On the basis of stretching ability it is of 2 types –


(ii)
Non-Stretchable
N

Transitional Epithelium :– (Stretchable)
Transitional epithelium (urothelium) :
In this epithelium basement membrane becomes invisible during stretching.
In this epithelium 4-6 layers of cells are present.
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(i)
(i)
These different shape of cells appears only in resting stage. When this tissue is stretched,
all the cells become flattened.
Eg.

Renal pelvis

Ureter

Urinary ladder

Proximal part of male urethra.
Epithelial cells
A
Epithelium
Underlying
connective
tissue
(ii)

Underlying
connective
tissue
Non stretchable epithelium
On the basis of shape of the cells of outermost layer, it is of three types.
(a) Stratified squamous epithelium
(b) Stratified cuboidal epithelium
(c)
Stratified columnar epithelium
77

Structural Organisation in Animals (Animal Tissue)
®
(a) Stratified squamous epithelium


Innermost layer of cells are of cuboidal.


Middle layers are made up of polygonal cells.
Cells of outermost layer are scale like flat cells.

On the basis of presence of keratin protein in the outer most cells, this epithelium is
of two types :-

Keratinized stratified squamous epithelium :If keratin protein is present, cells become non nucleated and dead.

eg.
Epidermis of skin

Non Keratinized stratified squamous epithelium :If Keratin protein is absent. Cells are nucleated and Living.
eg.
It lines the moist surface of buccal cavity and Pharynx.

Stratified cuboidal epithelium
Cell of outermost layer are cube like, nucleated and living.

Inner linning of ducts of salivary glands and pancreatic duct.
(c)
Stratified columnar epithelium
N
(b)

LL
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Outermost layer is composed of pillar shaped cells, cells are nucleated. On the basis
of presence of cilia this epithelium is of 2 types 
Ciliated

Non ciliated
NON-STRETCHABLE EPITHELIUM
Top most-layer
Squamous
Nonkeratinised
Squamous
Keratinised
Living nucleated
flat cells
Dead non nucleated
flat cells
Keratin
Cuboidal
Cuboidal
cells
Columnar
Ciliated
Columnar
Non-Ciliated
Cilia
A
Middle 2 to 4
Layers of pear
shaped cells
Inner most layer
of cells are cube like
BEGINNER’S BOX
1.
Transitional epithelium is found in :(1) Renal pelvis & Ureter
(3) Upper part of male urethra
2.
(2) Urinary bladder
(4) All of above
Stratified squamous epithelium is found in :(1) Buccal cavity
78
COMPOUND EPITHELIUM
(2) Stomach
(3) Intestine
(4) Spleen
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Pre-Medical : Biology
4.
(1) Cuboidal epithelium
(2) Columnar epithelium
(3) Transitional epithelium
(4) Compound epithelium
Non keratinised stratified squamous epithelium is found in :(1) Skin
5.
(2) Stomach
7.
(3) Pharynx
(4) Intestine
(3) Intestine
(4) Trachea
Compound squamous epithelium occurs in :(1) Stomach
6.


Which of the following tissue covers moist surface of buccal cavity and pharynx?
(2) Phaynx
Epidermis of skin of vertebrates comprises :(1) Simple Epithelium
(2) Stratified Epithelium
(3) Transitional Epithelium
(4) Columnar Epithelium
Living cells without keratin is found in :(1) Hairs
(2) Feathers
N
3.
®
(3) Epidermis
(4) Buccal cavity
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04. GLANDS
A cell or a group of cells which secretes chemical substances are called glands.
All glands are composed of epithelial tissue.
On the basis of number of cells
(1) Unicellular glands
Eg. Goblet cells, Paneth cells
(2) Multicellular glands
E.g. All glands except
Goblet cells and Paneth cells
A
Some of the columnar or cuboidal cells get specialised for secretion and are called
glandular epithelium (Figure). They are mainly of two types: unicellular, consisting of
isolated glandular cells (goblet cells of the alimentary canal), and multicellular, consisting
of cluster of cells (salivary gland).
Unicellular
gland
Multicellular
gland
(a)
(b)
Old NCERT XI Page No. 102, Figure 7.2 (a) & (b)
79

Structural Organisation in Animals (Animal Tissue)
®
On the basis of nature of secretion glands are of 3 types

(a) Endocrine glands :- It does not have ducts their products called hormones and

secreted directly into the fluid bathing the gland.
e.g. : Thyroid, pituitary, thymus, pineal, parathyroid, adrenal
(b)
Exocrine gland :- Secretory duct present. Exocrine glands secrete mucus (Goblet
cells), saliva (Salivary glands), earwax (Ceruminous glands), oil (Sebaceous glands),
milk (Mammary glands), digestive enzymes (Gastric glands, Intestinal glands) and
other cell products.
(c)
Heterocrine/mixed gland :- Both endocrine & exocrine parts are present.
BEGINNER’S BOX
1.
Mucus cells (Goblet cells) :(3) Endocrine glands
2.
(2) Endoderm
(4) All the above
(2) Pineal gland
(3) Sebaceous gland (4) Mammary gland
Which of the following is an example of multicellular endocrine gland ?
(2) Pituitary gland
(3) Goblet cells
(2) Thyroid
(3) Mammary glands (4) Adrenal gland
A
(1) Salivary glands
5.
(3) Mesoderm
In which gland secretions are directly released into blood ?
(1) Sweat gland
4.
(4) Parietal cells of gastric glands
Glands of vertebrates are originated from :(1) Ectoderm
3.
GLANDS
(2) Multicellular glands
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(1) Unicellular gland
N
eg. : Pancreas, Gonads, Liver (largest gland).
(4) Gastric glands
Pick the odd one out :
(1) Thymus
05. CONNECTIVE TISSUE

Connective tissues are the most abundant and widely distributed in the body of complex
animals. They are named connective tissue because of their special function of linking and
supporting other tissues/organs of the body. They range from soft connective tissues to
specialised types, which include cartilage, bone, adipose, and blood.
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Pre-Medical : Biology
Connective tissue
(2) Dense connective
(1) Loose connective
tissue
tissue
(More matrix, less fibres) (More fibres, less matrix)
Areolar
tissue
Adipose
tissue


®
(3) Specialised C.T.
Skeletal C.T.
Fluid C.T.
Dense
irregular Matrix solid and Liquid and fibre
free matrix
mineralised
tissue
eg. Found eg. Cartilage eg. Blood & lymph
and bone
in skin
Dense regular
tissue
eg. Tendons
Ligaments
The functions of connective tissues are To connect structures.
2.
To form packing around organs.
3.
To form a supporting framework.
4.
To combat foreign toxins.
5.
To replace tissues which have been destroyed by injury.
N
1.
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CELLS AND FIBRES OF CONNECTIVE TISSUE PROPER
COLLAGEN FIBRES (WHITE-FIBRES)
FIBROBLAST
BLOOD CAPILLARY
A
• Primary function is to produce
protein fibres
• Secrete matrix of connective tissue
(Chief matrix producing cells)
(YELLOW-FIBRES)
ELASTIC FIBRES
• Composed of elastin proteins
• Branched but arranged singly
• Maximum elasticity is present
• Highly resistant to chemicals
• Made up of collagen protein
(most abundant protein in animal kingdom)
• Wavy, inelastic, tough fibres arranged in the form
of bundles
• It is a protein present in largest amount in human
body
RETICULAR FIBRES
• Composed of reticulin protein
• Highly branched fibres
• Delicate fibres
• Mainly found in lymphoid organs
MAST CELLS
• Small and amoeboid cells with S-shaped nucleus
• Secrete-histamine, serotonin, heparin and
matrix of connective tissue proper
MACROPHAGES/HISTEOCYTES
• Amoeboid cell, kidney shaped nucleus
• Phagocytic in nature
• Destroy bacteria and viruses by phagocytosis
• Also called scavengers of connective tissue because
they destroy dead ordamaged cells to clean
connective tissues
• Also called histeocytes
81

®
 BEGINNER’S BOX

1.
2.
3.
Structural Organisation in Animals (Animal Tissue)
CONNECTIVE TISSUE (CELLS & FIBRES)
Fibroblast secretes :(1) Matrix
(2) Fibres
(3) Both (1) & (2)
Histeocytes destroy bacteria by :(1) Phagocytosis
(3) Produces antibodies
(2) Produces Antitoxins
(4) Produces antigen
Mast cell secrete :(1) Anticoagulant : Heparin
(3) Vaso constrictor : Serotonin
(2) Vasodilator : Histamine
(4) All of the above
Yellow, white & Reticular fibres are made up of protein :(1) Elastin, Reticulin, Collagen respectively
(2) Reticulin, Elastin, Collagen respectively
(3) Collagen, Elastin, Reticulin protein respectively
(4) Elastin, Collagen, Reticulin protein respectively
5.
Yellow & White fibres occurs as :(1) Singly & Bundles respectively
(3) Bundles only
LL
E
6.
N
4.
During injury mast cell secrete:(1) Elastin
(2) Hirudin
(4) Cells
(2) Single only
(4) Network forms
(3) Heparin
(4) Serotonin
(1) LOOSE CONNECTIVE TISSUE

It is of two types :- Areolar and adipose connective tissue.
A

It has more matrix and less fibres.
The cells and fibres are loosely arranged in a semifluid ground substance.

(A) Areolar Connective Tissue

Also known as spongy connective tissue.

It is most widely distributed tissue in the body.

It contains fibroblasts (cells that produce and secrete fibres), macrophages and mast cells.

Mast cells, macrophages & fibroblasts are more in number.
Function :- It serves as a support framework for epithelium i.e. present beneath the skin.
(B) Adipose Connective Tissue

Adipose tissue is another type of loose connective tissue located mainly beneath the skin.

It contains adipocytes / fat cells abundantly.

82
The cells are specialised to store fats, the excess of nutrients which are not used
immediately are converted into fats and are stored in this tissue.

Pre-Medical : Biology


(2) DENSE / FIBROUS CONNECTIVE TISSUE
®

It contains more fibres and less matrix.

Fibres and fibroblast cells are compactly packed in dense connective tissue.

Orientation of fibres show a regular or irregular pattern and are called dense regular and
dense irregular tissue.
(A) Dense Regular Connective Tissue
LL
E
N
Collagen fibres
Collagen fibres
(a) Dense regular connective tissue
(b) Dense irregular connective tissue
Old NCERT XI Page No. 103, Figure No. 7.5 (a), (b)
Many parallel bundles of collagen fibres, rows of fibroblasts are present alternately
(Regular pattern)
Tendon :- A structure which connects muscle to bones.
A
(i)
Muscle
Tendon
Bone
Ligment
Tendon and Ligament
(ii)
Ligaments :- A structure which connects bones.
(B) Dense Irregular Connective Tissue
It is present in the skin.
83

®
 BEGINNER’S BOX

1.
(2) Ligaments
(3) Tendon
(4) Adipose tissue
Collagen fiber and fibroblast arrangement is irregular is :(1) Tendon
3.
TYPES OF CONNECTIVE TISSUE
Muscles are connected to Bone by means of :(1) Cartilage
2.
Structural Organisation in Animals (Animal Tissue)
(2) Ligament
(3) Dura mater
(4) 1 & 2 both
Which of the following is known as spongy connective tissue ?
(1) Dense fibrous connective tissue
(2) Adipose connective tissue
(3) Areolar connective tissue
(4) Reticular fibrous connective tissue
(B) VASCULAR CONNECTIVE TISSUE
LL
E
(A) SKELETAL CONNECTIVE TISSUE
N
(3) SPECIALISED CONNECTIVE TISSUE
(i) Cartilage
(ii) Lymph
(i) Blood
(will study in circulatory system)
(ii) Bone
(A) SKELETAL CONNECTIVE TISSUE :

Matrix is dense & mineralised. Due to deposition of minerals it becomes hard.

Also known as Supporting Tissue i.e. Provide support to the body.

It is of 2 types :- Cartilage and Bone
(i)
Matrix (inter-cellular materials) is solid, pliable and can resists compression.
Cells of this tissue (Chondrocytes) are enclosed in small cavities (Lacuna), with in the
A

Cartilage :

matrix secreted by them.

1-4 chondrocytes (mature cells of cartilage) are found in one Lacuna.
Collagen fibers
Cartilage cells (chondrocyte)
Old NCERT XI Page No. 104, Figure No. 7.6 (a)
84

®
Pre-Medical : Biology

(1) Hyaline cartilage
(2) Elastic cartilage
(3) White fibrous cartilage
 of collagen fibres
• Matrix of this cartilage is glass • In the matrix of this cartilage • In matrix bundle
Types of Cartilage –
like clear or hyaline matrix
because fibres are completely
absent.
eg. Nasal septum.
'C' shaped rings of trachea and
bronchi.
Sternal part of ribs. (Costal
cartilage)
Laryngeal cartilage
Articular cartilage
yellow fibres form network
so it is highly flexible
cartilage of our body.
Eg. Tip of Nose
Ear Pinna
Epiglottis
are more in quantity so it is
strongest cartilage.
Eg. Pubic symphysis - Connects
both the pelvic halves with
each-other.
Intervertebral disc
BEGINNER’S BOX
3.
4.
5.
(3) Calcified cartilage (4) Elastic cartilage
(3) Epiglottis
Strongest cartilage is :(1) White fibrous cartilage
(3) Hyaline cartilage
(4) Eustachian tubes
(2) Elastic cartilage
(4) Calcified cartilage
Epiglottis is composed of :(1) Hyaline cartilage (2) Calcified cartilage (3) Both (1) & (2)
(4) Elastic cartilage
Which cartilage is present in external ear pinna ?
(1) Hyaline
(2) Elastic
(3) White fibrous
(4) Calcified
Solid, pliable & compression resistance like characterstics of intercelluar matrix is found in :(1) Bones of arm
(2) Radius bone
(3) Cartilage between adjacent bones of vertebral column
(4) Humerus & femur bones
A
6.
Hyaline cartilage found in :(1) Ear pinna
(2) Tracheal Rings
N
2.
Glass like cartilage is :(1) Hyaline cartilage (2) Fibrous cartilage
LL
E
1.
CARTILAGE
(ii)
Bone :

Mature cell of bone is called Osteocyte which is
found in lacuna. Only one osteocyte is found in
one lacuna.

Bones have a hard and non-pliable ground
substance rich in Ca+2 salts and collagen fibres
which gives bone its strength.
(b) Bone
Old NCERT XI Page No. 104,
Figure No. 7.6 (b)
85

Structural Organisation in Animals (Animal Tissue)
®
of bone :
 Functions

It is the main tissue that provide structural framework to the body.


Bones support and protect softer tissues and organs.






In all connective tissues except blood, the cells secrete fibres of structural proteins called
collagen or elastin or reticulin.
The fibres provide strength (collagen fibres), elasticity (elastin fibres) and flexibility to the
tissue.
Connective tissue is mesodermal in origin
Cells of connective tissue also secrete modified polysaccharide or mucopolysaccharides
like hyaluronic acid, which accumulate between cells and fibres and acts as matrix
(ground substance).
N

Limb bones, such as the long bones of the legs, serve weight bearing functions.
They also interact with skeletal muscles attached to them, to bring about
movements.
The bone marrow in some bones is the site of production of blood cells.
LL
E
BEGINNER’S BOX
ANSWERS KEY
INTRODUCTION & EPITHELIAL TISSUE
Que.
Ans.
1
4
2
4
3
1
4
4
TYPES OF EPITHELIAL TISSUE
Que.
Ans.
1
3
2
1
3
4
4
3
5
3
COMPOUND EPITHELIUM
A
Que.
Ans.
1
4
2
1
3
4
4
3
5
2
6
2
4
2
5
3
GLANDS
Que.
Ans.
1
1
2
4
3
2
CONNECTIVE TISSUE (CELLS & FIBRES)
Que.
Ans.
1
3
2
1
3
4
4
4
5
1
6
4
TYPES OF CONNECTIVE TISSUE
Que.
Ans.
1
3
2
3
3
3
CARTILAGE
Que.
Ans.
86
1
1
2
2
3
1
4
4
5
2
6
3
7
4