Tissues
A group of cells more or less same in structure, Size and shape and having the same function are called a
Tissue.ie. a cluster of cells at a definite place in the body performing a specific function. Plant and Animal
body are made up of tissues.
Plant tissues are two types: (A) Meristematic Tissues or Meristems. Tissue capable of cell division and growth. They are :(1) Apical meristem – Growing tips of root and stem
(2) Lateral Meristem – Divides in tangential form increasing the thickness of plant. Cambium and
Cork cambium are examples
(3) Intercalary meristem – Part of apical meristem found on the base of leaves or nodes which divide
and increase the height of plant.
(B) Permanent tissue:
(a) Simple Tissues - made up of one type of cells - They are
Name of
tissie
parenchyma
Collenchyma
Sclerenchyma
Nature
Living with inter cellular
space, Vacuolated
Living , with or without
intercellular spaceVacuolated
No intercellular space
Shape
Round, Oval or Polygonal
Polygonal
Irregular shape/
polyhedral
Cell wall
Thin uniform cellulose wall
Irrgularly thickened on
Thick lignified walls
the corners with cellulose
Cytoplasm
Living,Chlorophyl
Living – may or may not
have Chlorophyll
Dead clls
Functions
PhotosynthesisChlorenchyma.
Prpvide Support
,Flexibility,
elasticity,Tensil strenght
and Some time
Photosynthetic.
Mechanical Strength,
Rigidity, Grittiness to
fruit pulp
Below the epidermis of
leaf ,Petiole.
Stem, Root and
fruits,- Coconut husk
etc.
Floating - Aerenchyma
Occurrence Spongy tissue of leaf. Cortex
of stem
(b) Complex tissues : Which are made up of more than one types of cells . They are
Xylem ( Conducting water and minerals – Only upward) mainly made up of 4 types of cells
Tracheids
Narrow, Walls
more lignified
with lignin,, nonliving, with
tapering ends and
placed end to
end.Conduct
water and
minerals
mechanical
support.
Vessels
Xylem Fibres
Xylem Parenchyma
Narrow, Non-living,
lignified moderately,
very long, tubular, cells
are placed end-to-end
almost dissolved the
transverse
walls.Conduction of
water and minerals and
mechanical support
Sclerenchymatous dead
cells, thickened
walls,elongatedand
pointed ends.
Mechanical Support
Living, thin walled cells. Storage of
starch and sideways conduction of
water.
Phloem ( Conduct food up and down) also made up of 4 types of cells. ( Bast cells)
Sieve tube
Companion cells
Phloem fibres
Phloem
Parenchyma
Living , thin walled
elongated,Placed end-toend with porous transverse
walls (sieve plates)
Living, narrow,
nucleated,elongated cells
attached with sieve tube by
sideways pores and with
dense cytoplasm
Dead, Pointed ,
elongated ,lignified
and
sclerenchymatous
cells.
Living and
found
intermingled
with sieve
tubes
Plant Tissues
Meristematic tissue
Apical
Lateral
Permanent Tissue
Intercalary
Simple Tissues
Complex Tissues
Parenchyma Collenchyma
Sclerenchyma
Xylam
Phloem
(Tracheids, Vessels, X-fibres,X-Parenchyma
Fibres
Sclereids
(Ceive tube, Companion cells, Ph.Fibres, Ph.Parenchyma)
Animal tissues :- 1. Epithelial 2. Connective 3. Muscular 4. Nervous
Epithelial tissue/Covering tissues/protective tissue : Without inter-celular space, Cells lie upon a noncellular base layer made of special protein matrix known as Collagen. They are
Squamous Epithelium
Cuboidal
Epithelium
Columnar Epithelium
Celiated
Epithelium
Single layered,
flat,thin,polygonal or
irreular cells like tiles on a
floor. Found on the lining
of mouth oesophagus,
blood and lymph vessels,
ducts of glands. Protective
and diffusion in function
multi-layered squamous
epithelium is called
stratified epithelium.
Cube-shaped
cells, found as
lining of salivary,
thyroid and
sweat glands and
on the inner
lining of oviduct
and sperm
producing
tubules.
Longer-pillar like- cells,having
microvilli(blood capillaries) on their
free ends. Found on the inner lining of
alimentary canal from stomache to
rectum.Doing absorption, secretion
and protection . Inwardly folded
multicellular columnar epithelial
tissue is called Glandular epithelium.
Found inner to the Endocrine and
Exocrine glands.
These are
Cuboidal or
columnar cells
with numerous
hair like celia on
their free ends.
Connective Tissue: Connect/bind other tissues or organs together. In all types of connectives the cells areembeded
(placed) in an intercellular ,Jelly like, Fluid,Dense or rigid Matrix.Matrix differs according to the types of connective
tissue.
(a) Connective tissue porper
1. Areolar (loose ) tissue: having jelly like matrix with white collagen fibres or yellow elastin fibres and with
irregular cells like mast cells, fibroblast, and macrophages. Found between the skin and muscles,around
blood vessels and nerves and in the bone marrow. Functions as support- packing materioals between various
structures of the body, repair and phagocytic.
2. Adipose Tissue: Having matrix of large oval fat cells or adipocytes.As in the matrix of areolar tissue here the
matrix has Fat globules. Found beneath the skin, around kidney and bone marrow. Acts as a cusion to
position the internal organs like kidney, eye balls , Acts as shoke absorber and regulate body temperature.
3. Dense regular conective tissue: Composed of densely packed and ordered fibrous cells. They are:
(i) Tendons: Made up of inelastic dense ,cord-like collagen fibres bounded by areolar connective
tissues. It is thick ,tough and non-elastic tissue with collagen protein. It connect skeletal
muscles to bones
(ii) Ligaments: Formed of Yellow Elastin fibrres branched in different directions with less fluid. It is
strong, elastic(with elastin protein) and connect bone to bone
(b) Skeletal Tissue: It is a mineralised, hardened supporting connective tissue. They are
(1)Cartilage: With extensive (loose) matrix called Chondrion in which the cartilage cells or Chondrocytes and
embeded. It is flexible. Found in nose tip, Ear pinna, Rings or trachea, end of long bones and ribs.
(2)Bones: With hard and rigid matrix made up of organic Ossein protein( 30%) and inorganic like Calcium phosphate,
calcium carbonate and magnesium phosphate( 70% ). The rigid matrix is arranged as concentric rings called
lamellae between which bone cells called Osteocytes, are placed and in the centre a canal called haversian
canal. The osteocytes are present in a cluid space calle lacunae. Long bones contains bone marrow.
Difference between bone ad cartilage
Cartilage
Matrix not arranged in lamellae
Bone
Matrix arranged in lamellae
Matrix is composed of a firm, but flexibe material Matrix composed of tough, inflexible material
called chondrion
clled ossein
Bone Marrow is absent
Bone Marrow is present in long bones
Blood Vessels are abse nt
Blood vessels are present
Chondrocytes are Oval and devoid of Processes
Osteocytes are irregular and give up off branching
processes.
(c ) Fluid connective tissue ( Also called Vascular tissue)
Features of Fluid connective tissues: - Matrix is in fluid form and lacks fibres and not secreted by cells
present in it. They have no power of cell division.
Fluid tissues are of two types: Blood and Lymph
(a)Blood: mde up of Liquid portion called Plasma and Solid portion called Blood corpuscels
Plasma: Straw coloured, 90% water and rest –Protein, ions, Lipids , Glucose, Hrmones etc.
Blood cells are RBC, WBC and Platelets.
RBC ( Erythrocytes): Biconcave cell without nuclus. Middle contains and iron protein compouond called
Haemoglobing which functions as Oxygen carrier.Mitochondria and ER degenerate in matured RBC.
WBC (Leucocytes): Nucleated, White, motile with irregular shape.They may be granulocytes in the form of
Eosinophils with bilobed nucleus, Basophils with 2-3 lobed nucleus and Neutrophils with 3-5 lobed nucleus or
Agranulocytes including Monocytes and Immunocytes ( Lymphocytes)
Blood Platelets: Colourless, Round or Oval biconvex disc shaped cells without nucleus.
(c) Lymph: Formed by Squeezing out from cells and blood vessels as inter cellulalr fluid. Contains More WBC but no
RBC and Platelets. With Glucose, Salts, Vitamins and Amino acids.
Muscular Tissues: Which help in the movements of body by Contraction and Relaxation. They are:
Difference between blood and lymph
Blood
Lymph
1
Red in colour
Straw yellow in colour/hyaline
2
Erythroccytes are present
Erythrocytes are absent
3
Haemoglobin is present
Heamoglobin is absent
4
Contains many plasma proteins
Absent or very less in concentration
5
Calcium and Phosphorous
concentration is very high
Low concentration of Calcium and Phosphorous
concentration
6
It flows in blood vessels
Lows in lymph vessels and occupy inter cellular
space
(1) Striateed muscles: Called Voluntary /striped muscles/Skeletal muscles.
The cells –fibres- are long cylindrical, non-tapering un branched and multi-nucleate. Fibres are covered by
sarcolemma having acoenocytic plasma called sarcoplasm. This muscle has alternate darkand light striations
(bands). Found in Lymbs, Abdominal wall, Diaphragm, tongue etc.Helps in locomotion and Voluntary
movements of our body parts.
(2) Unstriated muscle: Called smooth, Visceral or involuntary muscles.
Smooth, Spindle shaped elongated cells with a transparent plasma membrane and central nNucleus held
together by connective tissue . Found on the walls of stomach, intestine , Recttum, Arteries,Bronchioles,
Genetal ducts, Urinary ducts.
(3) Cardiac muscle: Functionally unstriated and structurally striated with branched fibres forming a network.
They are Longitudinal myofibrils arrangeed with abundant loose connective tissues and rich supply of blood
capillaries. Found only in the walls of heart.
Difference between Muscular tissues.
Striated Muscles
Unstriated Muscles
Cardiac Muscles
1 Striations or bands preset
Striations or bands absent
Striations present
2 Voluntary
Involuntary
Involuntary
3 Fibres cylindrical
Fibres spindle -shaped
Fibres cylindrical
4 Sarcolemma present
Sarcolemma absent
Sarcolemma present
5 Multinucleate cells
Single nucleated
Single nucleus
6.
Fibres unbranched
Fibres branched
Fibres unbranched
7 Intercalated disc abset
Intercalated dis absent
Intercalatedisc present
8. Contraction rapid and Powerful Contractrion slow and Rythmic Contraction moderate and Rythmic
Nervous Tissue: A special type of tissue to receive and transmit messages. Made up of cells called Nerve
cells or Neurons. Found brain, Spinal cord and Nerve ganglion
Animal Tissue
1.Epithelial tissue
2. Connective tissue
a)Squamous .b)Cuboidal . c) Columnar. d) Ciliated. e )Glandular
3.Muscular tissue
a.Striated
4. Nervous tissue
2. Unstrited
(Visceral )
Muscl)
Connective tissue Proper
Skeletal tissue
Areolar Adipose Dense regular Cartelage
Tendones (Muscle to bones)
Bone
Fluid Connective tissue (Vasculaar tissue)
Blood
Ligaments (Bones to bones)
Lymph
3. Cardiac
(Heart