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and
and
Tissue culture
What is tissue culture?
What is tissue culture?
blocksCells
of life.
areA the
tissue
building
is a group
blocksofof life. A tissue is a group of
g a specifi
similar
c function
cells performing
and an organ
a specifi
is a c function and an organ is a
ming agroup
specifiofc tissues
function.
performing a specific function.
Tissue culture involves the in vitro growth
Tissueofculture
cells or
involves
tissuesthe
separate
in vitrofrom
growt
an organism. The liquid or semi-solidanculture
organism.
media
The
must
liquid
beor
maintained
semi-solidatcu
Xylem
the correct temperature, pH and osmotic
the correct
potential
temperature,
and must contain
pH and all
osmotic
the
Phloem
nutrients the
particular cells require: amino
nutrients
acids,
the glucose,
particularminerals,
cells require:
growth
amin
factors, oxygen etc. The growth factors
factors,
used
oxygen
in these
etc. media
The growth
are often
factor
Vascular
derived from animal
derived
serum.
from
However,
animal blood,
this increases
such asrisk
calf s
Tissueblood, such as calf
of pathogen transmission and alternatives
of pathogen
have now
transmission
been developed.
and alternative
Ground
The aim of tissue engineering is to repair
The aim
or replace
of tissuewhole
engineering
tissues is
such
to repair
as
Tissue
Xylemblood vessels, bladder,
bone, cartilage, blood vessels, bladder,
bone,
etc.
cartilage,
Xylem
ferentWhat
types
are
ofthe
tissue?
different types of tissue?
Cells
are
theand
building
blocks
life.andAplants,
tissue
pes of tissue
There
inare
both
many
animals
different
types
plants,ofeach
tissue
in both of
animals
eachis a group of
s.
with
very different
similar
cellsfunctions.
performing a specific function and an organ is a
main types
In group
humans,
of tissue:of
there
are four main
types of tissue:
tissues
performing
a specific function.
cells that
Epithelial
cover organ
tissue surfaces
– layers of
such
cells
asthat
the cover organ surfaces such as the
the inner
surface
liningof ofthetheskin
digestive
or the tract.
inner lining of the digestive tract.
protection,
Epithelial
secretion,
tissues
andserve
absorption.
for protection, secretion, and absorption.
Phloem
Vascular
Tissue
Ground
Tissue
Phloem
What are the different types of tissue?
How Dermal
doesTissue
tissue culture
Howwork?
does tissue culture
Dermal Tissue
Vascular
Thereconnects,
are
many
types ofconnects,
tissue inbinds
bothoranimals
name suggests,
Connective
tissue
–binds
asdifferent
theorname
separates
suggests,
separatesand plants, each
ood and bone.
tissues
e.g. blood
and bone.
with and
veryorgans
different
functions.
Fig.2
Outline of plant tissue
and
Tissue culture
Tissueits
culture
applications
its application
Fig.2
Usually the initial tissue sample isUsually
minced,the
and
initial
thentissue
digested
sample
withisanmin
Tissue
enzyme such as trypsin to remove
enzyme
the extracellular
such as
trypsin
matrix to
that
remove
holds th
the cells together. After that, the cells
the cells
are free
together.
floating,
After
and
that,
extracted
the cells
Ground
using centrifugation.
using centrifugation.
Outline of plant tissue
d groupsMuscle
of cellstissue
that can
– specialised
contract and
groups
exert of
a cells that can contract and exert a
In
there
four
main
types tissue:
of tissue:
hree type
pulling
of humans,
muscle
force.tissue:
There
smooth
areare
three
muscle,
type
of muscle
smooth muscle,
Tissue
Cells are then implanted or ‘seeded’Cells
into are
an artifi
thencial
implanted
structure
oror
‘seeded’
scaffoldinto
r liningswhich
of organs;
is found
skeletal
in the
muscle,
inner linings
which is
of organs;
skeletal
muscle, which is
The
Skin
The
Epithelial
tissue
–
layers
of
cells
that
cover
organ surfaces such
asSkin
the
that is capable of supporting a three-dimensional
that is capabletissue.
of supporting a three-dim
ones andattached
facilitates
to movement;
articulated bones
and cardiac
and facilitates movement; and cardiac
The
skin
is
the
body’s
largest
organ.
The
It
skin
is
made
is
the
up
body’s
of
layers
largest
of
epithelial
organ.
It
is
made
up
of
layers
of
epithelial
surface
of thetissue
skin
orheart.
the inner lining of the digestive tract.
of the heart.
muscle
– the muscle
of the
If cultured tissues are to be used for
If cultured
tissue reconstruction,
tissues are tothe
be scaffolds
used for tis
tissues.
tissues.
Epithelial tissues serve for protection,
secretion, and absorption.
must be biocompatible; it is also desirable
must beDermal
that
biocompatible;
they Tissue
be absorbed
it is also
bydesira
the
ming the
Nervous
brain, spinal
tissue –cord
cellsand
forming
peripheral
the brain, spinal cord and peripheral
The
skin
consists
of
three
primary
layers:
The
skin
the
consists
epidermis,
of
three
which
primary
acts
as
layers:
a
the
epidermis,
which
acts
as
a
surrounding tissues and not require surrounding
surgical removal.
tissues
The
and
scaffold
not require
should
surg
of neurons,
nervous
whichsystem.
transmit
It consists
electricalofimpulses
which transmit electrical impulses
Connective
tissue
– as neurons,
the name
suggests,
connects,
binds
or the
separates
barrier
to
moisture
and
infection;
barrier
dermis,
to
moisture
which
cushions
and
infection;
the
body
the
dermis,
which
cushions
the
body
degrade at roughly the same rate asdegrade
the newat
tissue
roughly
develops.
the same rate as the
non-neuronal
and neuroglia,
cells that which
aid and
are
participate
non-neuronal
in cells that aid and participate in
from
stress
and
strain
and
contains
from
the
stress
nails,
and
hair
strain
follicles,
and
sebaceous
contains
the
nails,
hair
follicles,
sebaceous
tissues
and
organs
e.g.
blood
and
bone.
s aroundthe
therapid
body.transfer of signals around the body.
glands etc; and the hypodermis (also
glands
called
etc;the
andsubcutaneous
the hypodermis
(also called
thetissue
subcutaneous tissue),
Fig.2 tissue),
Outline
of plant
What
are
the
applications
Whatofare
tissue
the application
culture?
Muscle tissue – specialised groupswhich
of cells
can contract
and
exert
aas insulation
acts that
as insulation
and protects
which
the
acts
internal
organs from
andvariations
protects the internal
organs
from
variations
One of the most important therapeutic
Oneapplications
of the most of
important
tissue culture
therapeutic
is in a
in temperature.
temperature.
pulling force. There are three type
of muscle tissue: smoothin muscle,
skin grafting for patients with seriousskin
burns.
grafting
Burns
forare
patients
traditionally
with serious
treatedbur
which is found in the inner liningsAsofone
organs;
skeletal
which
is
of the body’s
majormuscle,
organs,As
the
one
skinofhas
the abody’s
significant
majorrole
organs,
to play
the skin has a significant role to play
by taking a thin layer of skin fromby
antaking
undamaged
a thin layer
area of
known
skin as
from
thean
in homeostasis
the maintenance
ofinthe
homeostasis
internal environment
– the maintenance
of the body
of the internal environment of the body
attached to articulated bones and
facilitates –movement;
and
cardiac
donor site, and placing it on burn area.
donorInsite,
cases
andofplacing
severeitburns
on burn
there
area
The
is
the
body’s
largest
organ.
It
is
made
up
of
layers
of
epithelial
in a suitable state for efficient tissuein
cell
a suitable
metabolism.
stateItfor
plays
effi
cient
an skin
important
tissue
cell
metabolism.
It plays an
important
muscle – the muscle tissue of the heart.
may be few donor sites. Skin graftsmay
frombeother
few donor
peoplesites.
– allografts
Skin grafts
– canfrom
role in temperature regulation and isrole
alsoinpartly
temperature
responsible
regulation
for
protecting
and
is
also
partly
responsible
for
protecting
tissues.
be used as temporary dressings, but
beare
used
eventually
as temporary
rejected.
dressings, but ar
the brain,
body against
pathogens.
Whenperipheral
the
thebody
skin is
against
damaged
pathogens.
throughWhen
cuts or
the skin is damaged through cuts or
Nervous tissue – cells forming the
spinal
cord and
In
the
mid-1970s,
researchers
at
Harvard
In
the
mid-1970s,
University
discovered
researchers
at Harvar
they
burns the risk of infection is greatlyburns
increased.
the risk
Skin
of infection
tissue
that
is
has
greatly
been
increased.
Skin
tissue
that
has
been
The skin consists of three primary layers: the epidermis, which acts asthat
a
nervous system.
neurons,
which
transmit
impulses
CONNECTIVE
EPITHELIAL
TISSUE
TISSUE It consists of
EPITHELIAL
TISSUE
could
achieveasgrowth
couldofachieve
dermalgrowth
cells inand
vitroproliferation
in order
damaged
beyond
repairelectrical
must be removed
damaged
and
beyond
replaced
repairasmust
quickly
be removed
as
and
replaced
quicklyand
as proliferation
barrier
to
moisture
and
infection;
the
dermis,
which
cushions
the
body
and neuroglia, which are non-neuronal
cells
that aidprotective
and participate
in a time
to produce
a keratinising,
to produce
skin epithelium.
a keratinising,
Keratin
transplantab
is the
possible
by a suitable
layer
possible
until such
by
suitable
as new
protective
skin grows
layer until such
time as new
skin growstransplantable
from grafted
stress toand
strain
contains
theprotein
nails,found
hair follicles,
sebaceous
tough,and
insoluble
fibrous
tough,
ininsoluble
skin, hair
fibrous
and nails.
proteinIt foun
is
is cultured
cultured
underlying
and surgically
tissue.
the underlying
tissue.
the rapid transfer of signals aroundorthe
body. and surgically graftedortoisthe
glands etc; and the
(also
calledinthe
thehypodermis
structural matrix
of keratin
the
the subcutaneous
structural
epidermismatrix
that makes
oftissue),
keratin
the in
skin
the
The epidermis provides a relativelyThe
dryepidermis
and impermeable
provides
barrier
a relatively
to fluiddry and impermeable barrier to fluid
almost and
waterproof.
almost
waterproof.
which
acts
as insulation
protects
the internal
organs
from variations
loss. Loss of this function in burnsloss.
contributes
Loss ofto
this
thefunction
massive
inflburns
uid
loss
contributes
to the massive
fluid loss
in temperature.
The Harvard researchers were ableThe
to expand
Harvarda researchers
small sample
were
of skin
abletoto e
and consequent dehydration.
and consequent dehydration.
over 10,000 times its original size over
in a short
10,000time,
times
making
its original
the process
size in a
As one of the Hair
body’s
majorfororgans,
the skinfrom
hassevere,
a signifi
role
to play
Hair Folicle
Folicle
valuable
patients suffering
valuable
third
forcant
patients
degree
burns,
suffering
where
fromthe
seve
MUSCLE
NERVOUS
TISSUE
TISSUE
NERVOUS TISSUE
for skin grafting
low.
potential
for skin grafting
is low.
in homeostasis – thepotential
maintenance
of theisinternal
environment
of the body
The Skin
sues foundFig.
In humans
1 Four main types of tissues found In humans
BURN
DEPTH
1˚
BU RN
D E PTH
1˚
d into three
Plant
broad
tissues
tissue
cantypes,
be divided
whichinto
together
three broad tissue types, which together
mass. are often referred to as biomass.
CONNECTIVE TISSUE
EPITHELIAL
TISSUE
3˚
ost layerDermal
of cellstissue
forming
– the
theoutermost
outer surface
layerofof cells forming the outer surface of
g plant body.
the leaves and of the young plant body.
s of cells
Vascular
that transport
tissue – flconsists
uid and nutrients
of cells that transport fluid
3˚ and nutrients
ary components
within the
of plant.
vascular
Thetissue
primary
arecomponents
xylem
of vascular tissue are xylem
4˚
and phloem.
3˚
3˚
4˚
SKIN LAYE R
SKIN LAYE R
in a suitable state for
efficient
tissue
plays
anthe
important
Further
work over
thecell
past metabolism.
thirty years
FurtherItwork
over
past thirty years
led toEpidermis
advances
the cell
growth
has led to advances
in the cell growth
role in temperature has
regulation
and isinalso
partly
responsible
for protecting
process, reducing
thethe
amount
process, reducing
the amount
the body against pathogens.
When
skinofistime
damaged
through
cuts orof time
it takes to culture the skin, while
it takes to culture the skin, while
Dermis
Dermis
burns the risk of infection
is
greatly
increased.
Skin
tissue
that
has
been
increasing the amount and size of the
increasing the amount and size of the
damaged beyond repair
be removed
and
replaced
as quickly
grafts must
available.
Because these
grafts
available.
Becauseasthese
are protective
autologous
cells
aretime
autologous
patient’s
possible by a suitable
layer(the
untilpatient’s
such
as newcells
skin(the
grows
Subcutaneous
Subcutaneous
Layer
Layer the risk of
own cells),
own cells),
the risk of rejection
or is cultured and surgically
grafted to therejection
underlying
tissue.
Epidermis
and
Muscle
hose primary
Ground function
tissue – istissue
the manufacture
whose primary function is the manufacture
nthesis; ofit nutrients
can also by
andphotosynthesis;
store nutrients.it can also and store nutrients.
Sweat Gland
from the
Ground
meristem
tissueand
develops
consistsfrom
of the meristem and consists of the
Fig.3 Skin showing levels of burning Fig.3 Skin showing levels of burning
and sclerenchyma
parenchyma,
cells.
collenchyma and sclerenchyma cells.
MUSCLE TISSUE
pathogen
Muscle
transmission
with
and
pathogen
transmission
on patients who have burns covering
on patients
whograft
have burns covering
Fig.4 Skin
more than 30% of their bodies.
more than 30% of their bodies.
Hair Folicle
NERVOUS TISSUE
BURN
DE PTH
Fig. 1 Four main types of tissues found In humans
SKIN LAYER
Epidermis
1˚
Plant tissues can be divided into three broad tissue types, which together
are often referred to as biomass.
Dermis
3˚
Dermal tissue – the outermost layer of cells forming the outer surface of
the leaves and of the young plant body.
Vascular tissue – consists of cells that transport fluid and nutrients
within the plant. The primary components of vascular tissue are xylem
and phloem.
Ground tissue – tissue whose primary function is the manufacture
of nutrients by photosynthesis; it can also and store nutrients.
Ground tissue develops from the meristem and consists of the
parenchyma, collenchyma and sclerenchyma cells.
with
autografts
is low.
autografts is low.
The epidermis provides
a relatively
dry and impermeable
barrier to fluid
loss. Loss of this function
in burns
contributes
to the
massive
fluidasloss
This process
is known
as cultured
This
process
is known
cultured
epithelial autograft (CEA) and is used
epithelial autograft (CEA) and is used
and consequent
Sweat Glanddehydration.
Subcutaneous
Layer
3˚
Muscle
4˚
Sweat Gland
Fig.3
Skin showing levels of burning
and
and
SCIENCE TECHNOLOGY
SECOND
EDITION
EDITION
ACTION THIRD
AND
its applications
IN
and
Tissue culture
Tissueits
culture
applications
its application
What is tissue culture?
What is tissue culture?
blocksCells
of life.
areA the
tissue
building
is a group
blocksofof life. A tissue is a group of
g a specifi
similar
c function
cells performing
and an organ
a specifi
is a c function and an organ is a
ming agroup
specifiofc tissues
function.
performing a specific function.
Xylem
Phloem
ferentWhat
types
are
ofthe
tissue?
different types of tissue?
What is tissue culture?
pes of tissue
Thereinare
both
many
animals
different
and types
plants,ofeach
tissue in both animals and plants, each
s.
with very different functions.
Tissue culture involves the in vitro growth of cells or tissues separate from
main types
In humans,
oforganism.
tissue: thereThe
are liquid
four main
of tissue:
an
or types
semi-solid
culture media must be maintained at
the
correct
temperature,
pH
and
osmotic
and as
must
cells that
Epithelial
cover
organ
tissue
surfaces
– layers of
such
cells
asthat
the cover
organpotential
surfaces such
the contain all the
the inner
surface
liningofthe
ofthe
theskin
digestive
or cells
the tract.
inner lining
of acids,
the digestive
tract.
nutrients
particular
require:
amino
glucose,
minerals, growth
protection,
Epithelial
secretion,
tissues
andserve
absorption.
for protection, secretion, and absorption.
factors, oxygen etc. The growth factors used in these media are often
name suggests,
Connective
connects,
tissue
–binds
as the
orname
separates
suggests,
connects,
binds
or separates
derived
from
animal
blood,
such as calf
serum.
However,
this increases risk
ood and bone.
tissues and organs e.g. blood and bone.
Vascular
Tissue
Ground
Tissue
Dermal Tissue
Tissue culture involves the in vitro growth
Tissueofculture
cells or
involves
tissuesthe
separate
in vitrofrom
growt
an organism. The liquid or semi-solidanculture
organism.
media
The
must
liquid
beor
maintained
semi-solidatcu
Xylem
the correct temperature, pH and osmotic
the correct
potential
temperature,
and must contain
pH and all
osmotic
the
Phloem
nutrients the
particular cells require: amino
nutrients
acids,
the glucose,
particularminerals,
cells require:
growth
amin
factors, oxygen etc. The growth factors
factors,
used
oxygen
in these
etc. media
The growth
are often
factor
Vascular
derived from animal
derived
serum.
from
However,
animal blood,
this increases
such asrisk
calf s
Tissueblood, such as calf
of pathogen transmission and alternatives
of pathogen
have now
transmission
been developed.
and alternative
Ground
The aim of tissue engineering is to repair
The aim
or replace
of tissuewhole
engineering
tissues is
such
to repair
as
Tissue
bone, cartilage, blood vessels, bladder,
bone,
etc.
cartilage, blood vessels, bladder,
How Dermal
doesTissue
tissue culture
Howwork?
does tissue culture
Usually the initial tissue sample isUsually
minced,the
and
initial
thentissue
digested
sample
withisanmin
Genzyme is one ofenzyme
the world’s
leading biotechnology
companies
such as trypsin to remove
enzyme
the extracellular
such as trypsin
matrix to
that
remove
holds th
with more than 9000
employees.
The that,
company’s
goal
is to
make
the cells
together. After
the cells
the cells
are free
together.
floating,
After
and
that,
extracted
the cells
Fig.2 Outline of plant tissue
Fig.2 Outline of plant tissue
d groupsMuscle
of cellstissue
that can
– specialised
contract and
groups
exert of
a cells that can contract and exert a
using centrifugation.
using
centrifugation.
a major positive impact
on the lives of people
with
debilitating
The
aim
of tissue
repairtissue:
or replace
tissues such as
hree type
pulling
of muscle
force.
tissue:
There engineering
smooth
are three
muscle,
type is
ofto
muscle
smoothwhole
muscle,
diseases. The company
and
produces
innovative
Cells are thendesigns
implanted or
‘seeded’
Cells
into are
an artifi
then
cial
implanted
structure
oror
‘seeded’
scaffoldinto
r liningsbone,
which
of organs;
iscartilage,
found
skeletal
in the
muscle,
innervessels,
linings
which is
of bladder,
organs;
skeletal
muscle,
which
is
blood
etc.
The Skin
The Skin
is capable
of supporting
three-dimensional
that is capable
of supporting a three-dim
solutions for majorthat
unmet
medical
needsaof
patients
with tissue.
genetic
ones andattached
facilitates
to movement;
articulated bones
and cardiac
and facilitates movement; and cardiac
The
skin
is
the
body’s
largest
organ.
The
It
skin
is
made
is
the
up
body’s
of
layers
largest
of
epithelial
organ.
It
is
made
up
of
layers
of
epithelial
of the heart.
muscle – the muscle tissue of the heart.
and chronic debilitating
diseases.
Genzyme
a product
forare
the
If cultured
tissues are
to be usedhas
for
If cultured
tissue
reconstruction,
tissues
tothe
be scaffolds
used for tis
tissues.
tissues.
How
does
tissue
treatment of patients
severe skinit burns.
Itmust
is grown
from
mustwith
be biocompatible;
is also desirable
bethat
biocompatible;
they
be the
absorbed
it is also
bydesira
the
ming the
Nervous
brain, spinal
tissue
–cord
cells
and
forming
peripheral
theculture
brain, spinal work?
cord and peripheral
The
skin
consists
of
three
primary
layers:
The
skin
the
consists
epidermis,
of
three
which
primary
acts
as
layers:
a
the
epidermis,
which
acts
as
a
surgical removal.
tissues
The
and
scaffold
not require
should
surg
of neurons,
nervous
whichsystem.
transmit
It consists
electrical
ofimpulses
neurons,
which
transmit electrical
impulses
patients own skin.surrounding tissues and not require surrounding
Usually
the initial
tissue
sample
is minced,
and then
digested
with
an
barrier
to
moisture
and
infection;
the
barrier
dermis,
to
moisture
which
cushions
and
infection;
the
body
the
dermis,
which
cushions
the
body
degrade at roughly the same rate asdegrade
the newat
tissue
roughly
develops.
the same rate as the
non-neuronal
and neuroglia,
cells that which
aid and
are
participate
non-neuronal
in cells that aid and participate in
enzyme such as trypsin to removefrom
the stress
extracellular
matrix
thatfrom
holds
and
strain
and
contains
the
stress
nails,
and
hair
strain
follicles,
and
sebaceous
contains
the
nails,
hair
follicles,
sebaceous
Genzyme was founded in 1981 and has grown from a small starts aroundthe
therapid
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glands
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the cells together. After that, the cells
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upand
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What
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Whatofin
are
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$3 billion. Since its foundation, Genzyme has introduced a
of pathogen transmission and alternatives have now been developed.
in temperature.
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One of the most important therapeutic
Oneapplications
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cial structure
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antaking
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isrole
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be used as temporary dressings, but
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must be biocompatible; it is also desirable
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In
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In
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is
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uiddry and impermeable
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What are the applications
of tissue
almost
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uid loss
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and Development facility at Waterford to support clinical trial
One of the most important therapeutic
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The Harvard researchers were ableThe
to expand
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small sample
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andapplications
consequent dehydration.
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product manufacture.
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Genzyme
over 10,000 times its original size over
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skin grafting for patients with serious burns. Burns are traditionally treated
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SKIN LAYE R
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lled
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while
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mass. In
arethe
often
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biomass.
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mid-1970s,
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at Harvard University discovered that they
increasing
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ost layercould
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This process is known as cultured
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whose primary function is the manufacture
For more information
on the
work
Genzyme
check
epithelial autograft
(CEA)
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and store
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on patients
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Fig.4 Skin
www.genzyme.ie
or
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from the
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Skin showing levels of burning Fig.3 Skin showing levels of burning
more than 30% of their bodies.
more than 30% of their bodies.
and sclerenchyma
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valuable
for
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from severe,
potential for skin grafting is low.
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has led to advances in the cell growth
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it takes to culture the skin, while
increasing the amount and size of the
grafts available. Because these
are autologous cells (the patient’s
own cells), the risk of rejection
and pathogen transmission with
autografts is low.
This process is known as cultured
epithelial autograft (CEA) and is used
on patients who have burns covering
more than 30% of their bodies.
What are other applications
of tissue culture and engineering?
Once damaged, articular cartilage in joints such as the knees and hips,
does not have the ability to regenerate itself. Cartilage cells, known as
chondrocytes, can now be cultured and used in treating damaged
articular cartilage of the knee, in a process known as autologous
chondrocyte implantation (ACI).
Fig.4
Skin graft
In 2006, tissue engineering was used to produce seven artificially grown
bladders, which were implanted into patients.
and
and
Tissue culture
and
Tissue culture
Tissueits
culture
applications
its application
What is tissue culture?
What is tissue culture?
blocksCells
of life.
areA the
tissue
building
is a group
blocksofof life. A tissue is a group of
g a specifi
similar
c function
cells performing
and an organ
a specifi
is a c function and an organ is a
ming agroup
specifiofc tissues
function.
performing a specific function.
Tissue culture involves the in vitro growth
Tissueofculture
cells or
involves
tissuesthe
separate
in vitrofrom
growt
an organism. The liquid or semi-solidanculture
organism.
media
The
must
liquid
beor
maintained
semi-solidatcu
Xylem
the correct temperature, pH and osmotic
the correct
potential
temperature,
and must contain
pH and all
osmotic
the
Phloem
Phloem
nutrients the
particular cells require: amino
nutrients
acids,
the glucose,
particularminerals,
cells require:
growth
amin
factors, oxygen etc. The growth factors
factors,
used
oxygen
in these
etc. media
The growth
are often
factor
Vascular Certificate Science
Vascular
Junior
derived from animal
derived
serum.
from
However,
animal blood,
this increases
such asrisk
calf s
Tissue
Tissueblood, such as calf
of pathogen
transmission
and alternatives
pathogen
have
transmission
been
developed.
and alternative
OB47 – Carry out simple
activities
to show
theofpath
of now
water
through
Ground
Ground
plant
tissue, and show
thatof water
evaporates
the
oftissues
a leafis
The aim
tissue engineering
is tofrom
repair
The aim
or replace
ofsurface
tissuewhole
engineering
such
to repair
as
Tissue
Tissue
by transpiration
bone, cartilage, blood vessels, bladder,
bone,
etc.
cartilage, blood vessels, bladder,
Xylem
ferentWhat
types
are
ofthe
tissue?
different types of tissue?
Syllabus Reference
pes of tissue
Thereinare
both
many
animals
different
and types
plants,ofeach
tissue in both animals and plants, each
s.
with very different functions.
Certifi
cate
main types
InLeaving
humans,
of tissue: there
are four
mainBiology
types of tissue:
Unit
1.3.6
– surfaces
Structural
role
of biomolecules
cells that
Epithelial
cover
organ
tissue
– layers of
such
cells
asthat
the
cover organ surfaces such as the
the inner
surface
of ofthe
theskin
digestive
or the tract.
inner
lining of the digestive tract.
Unitlining
2.1.2
– Cell
structure
and function.
protection,
Epithelial
secretion,
tissues
andserve
absorption.
for protection, secretion, and absorption.
Dermal Tissue
Unit 2.4.1 – Tissues; Unit 2.4.2 – Organs; Unit 2.4.3 – Organ Systems.
How Dermal
doesTissue
tissue culture
Howwork?
does tissue culture
Usually the initial tissue sample isUsually
minced,the
and
initial
thentissue
digested
sample
withisanmin
True/False Questions
name suggests,
Connective
connects,
tissue
–binds
asExcretory
theorname
separates
suggests,
binds or separates
Unit 3.4.6
– The
Systemconnects,
in the Human
ood and bone.
tissues and organs e.g. blood and bone.
enzyme such as trypsin to remove
enzyme
the extracellular
such as trypsin
matrix to
that
remove
holds th
the cells
After10that,
the cells
the cells
are free
together.
floating,
After
that,
the cells
12 cells?
Fig.2 Outline of plant tissue
Fig.2 Outline of plant
(a)tissue
The average human
bodytogether.
contains
Tand
F extracted
Junior
cateand
Science
d groupsMuscle
of
cellstissue
thatCertifi
can
– specialised
contract
groups
exert of
a cells that can contract and exert a
using centrifugation.
using centrifugation.
hree type
pulling
of muscle
force.
tissue:
There
smooth
are three
muscle,
typethat
of muscle
tissue:
smooth muscle,
(b) The three types of plant tissue are together
Section
OB46
– understand
the xylem
transports
water and minerals
Cells are then implanted or ‘seeded’Cells
into are
an artifi
thencial
implanted
structure
oror
‘seeded’
scaffoldinto
r liningswhich
of organs;
is found
skeletal
in the
muscle,
inner linings
which is
of organs;
skeletal
muscle,
which
is
The Skin
The Skin
referred to as biomass?
T F a three-dim
infacilitates
the plant
and thatand
thecardiac
phloem
transports
food
that is capable of supporting a three-dimensional
that is capabletissue.
of supporting
ones andattached
to movement;
articulated bones
and facilitates movement; and cardiac
The
skin
is
the
body’s
largest
organ.
The
It
skin
is
made
is
the
up
body’s
of
layers
largest
of
epithelial
organ.
It
is
made
up
of
layers
of
epithelial
of the heart.
muscle – the muscle tissue of the heart.
(c) The skin is composed
of four
primary
layers?
F scaffolds
If cultured
tissues
are to be
used for
If cultured
tissue reconstruction,
tissues are T
tothe
be
used for tis
tissues.
tissues.
must be biocompatible;
must bethat
biocompatible;
they be absorbed
bydesira
the
ming the
Nervous
brain, spinal
tissue –cord
cellsand
forming
peripheral
the brain, spinal cord and peripheral
(d) “In vitro” means “inside
the body”? it is also desirable
T it Fis also
The
skin
consists
of
three
primary
layers:
The
skin
the
consists
epidermis,
of
three
which
primary
acts
as
layers:
a
the
epidermis,
which
acts
as
a
surrounding tissues and not require surrounding
surgical removal.
tissues
The
and
scaffold
not require
should
surg
of neurons,
nervous
whichsystem.
transmit
It consists
electricalofimpulses
neurons, which transmit electrical impulses
barrier
to
moisture
and
infection;
the
barrier
dermis,
to
moisture
which
cushions
and
infection;
the
body
the
dermis,
which
cushions
the
body
(e)
The
culturing
of
tissue
pieces
is
known
as
implant
culture?
T
F
degrade at roughly the same rate asdegrade
the newat
tissue
roughly
develops.
the same rate as the
non-neuronal
and neuroglia,
cells that which
aid and
are
participate
non-neuronal
in cells that aid and participate in
from
stress
and
strain
and
contains
from
the
stress
nails,
and
hair
strain
follicles,
and
sebaceous
contains
the
nails,
hair
follicles,
sebaceous
s aroundthe
therapid
body.transfer of signals around the body.
A growth
medium
cansubcutaneous
be liquid, solid
T F
glands etc; and the hypodermis (also
glands
called
etc;the
andsubcutaneous
the(f)
hypodermis
tissue),
(also
called the
tissue),or semi-solid?
On completing this section, the
student will be able to:
What
areenzyme
the
applications
Whatofare
tissue
the application
culture?
which acts as insulation and protects
which
the acts
internal
as insulation
organs
andvariations
protects
theexample
internal
organs
variations
(g)from
Trypsin
is an
of anfrom
used to dissolve
One of the most important therapeutic
Oneapplications
of the most of
important
tissue culture
therapeutic
is in a
in temperature.
in temperature.
• Define the terms cell; tissue; organ
the extracellular matrix?
Twith
F serious
skin grafting for patients with seriousskin
burns.
grafting
Burns
forare
patients
traditionally
treatedbur
As
one
of
the
body’s
major
organs,
As
the
one
skin
of
has
the
a
body’s
signifi
cant
major
role
organs,
to
play
the
skin
has
a
signifi
cant
role
to
play
• Explain the structure and function of the skin
by
taking
a thin layer
of skin of
from
antaking
undamaged
a thin layer
area Tof
known
skin as
from
thean
(h) Biodegradability
is not
a useful
property
a by
scaffold?
F
in homeostasis – the maintenance ofinthe
homeostasis
internal environment
– the maintenance
of the body
of the internal environment of the body
donor site, and placing it on burn area.
donorInsite,
cases
andofplacing
severeitburns
on burn
there
area
• Define the term tissue culture in a suitable state for efficient tissueincell
a suitable
metabolism.
stateItfor
plays
effi
cient
an
important
tissue
cell
metabolism.
It
plays
an
important
(i) Culture conditions
must
bedonor
exactly
same
may
be few
sites.the
Skin
graftsmay
frombeother
few donor
peoplesites.
– allografts
Skin grafts
– canfrom
role
in
temperature
regulation
and
is
role
also
in
partly
temperature
responsible
regulation
for
protecting
and
is
also
partly
responsible
for
protecting
• Name the tools used in tissue culture
for each cell type?
T
F
be used as temporary dressings, but
beare
used
eventually
as temporary
rejected.
dressings,
but ar
the body against pathogens. Whenthe
thebody
skin is
against
damaged
pathogens.
throughWhen
cuts or
the skin is damaged through cuts or
• Name two therapeutic application
of the
tissue
culture
InSkin
the
mid-1970s,
researchers
at Harvard
In the mid-1970s,
University discovered
researchers
at Harvar
they
burns
risk of
infection is greatlyburns
increased.
the risk
Skin
of infection
tissue
is has
greatly
been
increased.
tissue
that has
(j) that
Epidermal
cells are
also
known
as been
keratinocytes?
T F that
CONNECTIVE
EPITHELIAL TISSUE
TISSUE
EPITHELIAL TISSUE
could
achieveasgrowth
couldofachieve
dermalgrowth
cells inand
vitroproliferation
in order
damaged beyond repair must be removed
damagedand
beyond
replaced
repairasmust
quickly
be removed
as
and
replaced
quicklyand
as proliferation
• Explain in detail one applicationpossible
of tissue
engineering
(k)new
Skin
own
cells?
TKeratin
Ftransplantab
to the
produce
a keratinising,
transplantable
to produce
skin epithelium.
a keratinising,
is the
by a suitable protective layer
possible
until such
by a time
suitable
as
protective
skinallografts
grows
layer untiluse
such
timepatient’s
as new
skin
grows
tough, insoluble
tough, ininsoluble
skin, hair
fibrous
and
proteinIt foun
is
or is cultured and surgically graftedortoisthe
cultured
underlying
and surgically
tissue.
grafted is
to the
underlying
tissue. fibrous protein found
(l) Cartilage
self-regenerative?
T Fnails.
the structural matrix of keratin in the
the structural
epidermismatrix
that makes
of keratin
the in
skin
the
The epidermis provides a relativelyThe
dryepidermis
and impermeable
provides
barrier
a relatively
to fluiddry and impermeable barrier to fluid
almost waterproof.
almost waterproof.
loss. Loss of this function in burnsloss.
contributes
Loss ofto
this
thefunction
massive
in
fl
burns
uid
loss
contributes
to
the
massive
fl
uid
loss
Check your answers to these questions on www.sta.ie
The Harvard researchers were ableThe
to expand
Harvarda researchers
small sample
were
of skin
abletoto e
and consequent dehydration.
and consequent dehydration.
over 10,000 times its original size over
in a short
10,000time,
times
making
its original
the process
size in a
• A tissue is a group of cells performing a particular function
Hair Folicle
Hair Folicle
valuable for patients suffering from severe,
valuablethird
for patients
degree burns,
suffering
where
fromthe
seve
NERVOUS
TISSUE
NERVOUS TISSUE
potential for skin grafting is low.
potential for skin grafting is low.
•MUSCLE
FourTISSUE
main types of tissue
– epithelial, connective, muscle and
Learning Outcomes
General Learning Points
nervous
sues foundFig.
In humans
1 Four maintissue
types of tissues found In humans
BURN
DEPTH
BU RN
D E PTH
1˚
• Skin is made up of three layers of epithelial
tissues – epidermis, 1˚
d into three
Plant
broad
tissues
tissue
cantypes,
be divided
whichinto
together
three broad tissue types, which together
dermis
andtohypodermis
mass. are often
referred
as biomass.
•of cells
Tissue
is surface
thelayer
growth
offorming
tissues
from
ost layerDermal
tissue
forming
–culture
the
theoutermost
outer
ofof cells
theseparate
outer surface
of
under
controlled
g plant body.
the leaves
and
of the youngconditions
plant body.
3˚
an organism 3˚
s of cells
Vascular
transport
tissueengineering
– flconsists
uid and nutrients
ofcan
cellsbe
that
transport
fluid
nutrients portions
•thatTissue
used
to repair
or replace
3˚ and
ary components
withinwhole
the
of plant.
vascular
Thetissue
primary
arecomponents
xylem
of vascular tissue are xylem
tissues
4˚
and phloem.
of or 3˚
4˚
• Scaffolds are the structures that allow 3-D tissue formation
Examination Questions
SKIN LAYE R
SKIN LAYE R
Further work over the past thirty years
Further work over the past thirty years
has led toEpidermis
advances in the cell growth
has led to advances in the cell growth
2007 Leaving Certifi
cate
Higher
Level
process, reducing the amount of time
process, reducing the amount of time
it takes
to
culture
skin, while
it takes to culture the skin, while
The diagrams represent
twoDermis
forms
of athe
vascular
Dermis
the amount and size of the
increasing the amount and size of the
plant tissue, as seenincreasing
under the
microscope.
grafts available. Because these
grafts available. Because these
are autologous
cells (the patient’s
are autologous cells (the patient’s
Subcutaneous
Subcutaneous
(a) Name this vascular
tissue
Layer
Layer the risk of
own cells),
rejection
own cells), the risk of rejection
……………………………………........….
and pathogen
transmission with
and pathogen transmission with
Muscle
Muscle
autografts is low.
autografts is low.
Epidermis
(b) Identify the two forms of this tissue.
This process is known as cultured
This process is known as cultured
hose primary
Ground function
tissue – istissue
the manufacture
whose primary function is the manufacture
epithelial autograft (CEA) and is used
epithelial autograft (CEA) and is used
A …………………………………………..
Basic
requirements
be
nthesis; of•
it nutrients
can
alsocell
by
andphotosynthesis;
store nutrients.it e.g.
can oxygen,
also and pH,
storeosmosis
nutrients. etc. must
Sweat Gland
Sweat Gland
on patients who have burns covering
on patients
whograft
have burns covering
Fig.4 Skin
B ………………………………….............
from the
Ground
meristem
tissueand
develops
consists
from
of the meristem and consists of the
maintained
in
culture
Fig.3 Skin showing levels of burning Fig.3 Skin showing levels of burning
more than 30% of their bodies.
more than 30% of their bodies.
and sclerenchyma
parenchyma,
cells.
collenchyma and sclerenchyma cells.
• Tissue engineering has enabled skin grafting in patients with
severe burns
• Cultured epithelial autografts have low potential for rejection and
disease transmission
Student Activity
Mandatory Experiment:
Leaving Certificate Biology
Unit 2.1.2 Prepare and examine one animal cell and one plant cell (e.g.
own cheek cells, onion cells, Elodea leaf, potato tissue and moss)
unstained and stained using the light microscope (×100, ×400).
Unit 3.2.1 Prepare and examine microscopically the transverse section
of a dicotyledonous stem (×100, ×400).
(c) The walls of A and B are reinforced with a
hard material. Name this material ......................................................
(d) Where precisely is this vascular tissue found in the stem of a young
dicotyledonous plant? .........................................................................
(e) Name another vascular tissue ...........................................................
2006 Leaving Certificate Higher Level
The diagram shows part of a transverse
section through a dicotyledonous stem.
(i) Copy the diagram into your answer book
and identify each of the following by placing
the appropriate letter on your diagram:
phloem P, ground tissue G, xylem X, dermal
tissue D.
(ii) In which of the tissues that you have
identified are sugars mainly transported?
and
and
SCIENCE TECHNOLOGY
SECOND
EDITION
EDITION
ACTION THIRD
AND
its applications
IN
and
Tissue culture
Tissueits
culture
applications
its application
What is tissue culture?
What is tissue culture?
blocksCells
of life.
areA the
tissue
building
is a group
blocksofof life. A tissue is a group of
g a specifi
similar
c function
cells performing
and an organ
a specifi
is a c function and an organ is a
ming agroup
specifiofc tissues
function.
performing a specific function.
Xylem
Phloem
ferentWhat
types
are
ofthe
tissue?
different types of tissue?
2004
Leaving
Certifi
cate
Higher
Leveland plants, each
pes of tissue
Thereinare
both
many
animals
different
and
types
plants,
ofeach
tissue
in both animals
Tissue culture involves the in vitro growth
Tissueofculture
cells or
involves
tissuesthe
separate
in vitrofrom
growt
an organism. The liquid or semi-solidanculture
organism.
media
The
must
liquid
beor
maintained
semi-solidatcu
Xylem
the correct temperature, pH and osmotic
the correct
potential
temperature,
and must contain
pH and all
osmotic
the
Phloem
nutrients the
particular cells require: amino
nutrients
acids,
the glucose,
particularminerals,
cells require:
growth
amin
factors, oxygen etc. The growth factors
factors,
used
oxygen
in these
etc. media
The growth
are often
factor
Vascular
derived from animal
derived
serum.
from
However,
animal blood,
this increases
such asrisk
calf s
Tissueblood, such as calf
of pathogen transmission and alternatives
of pathogen
have now
transmission
been developed.
and alternative
Ground
(1850–1924)
The aim of tissue engineering is to repair
The aim
or replace
of tissuewhole
engineering
tissues is
such
to repair
as
Tissue
bone, cartilage, blood vessels, bladder,
bone,
etc.
cartilage, blood vessels, bladder,
Vascular
Biographical
Notes
Tissue
s.
with very different
Cardiac
musclefunctions.
may be described as a contractile tissue. Explain the
meaning
theare
underlined
term.
main types
In humans,
of tissue:of
there
four main types
of tissue:
Ground
Wilhelm
Roux
Tissue
Roux was born and educated in Jena, in Thuringia, Germany.
His special interest, which he called developmental mechanics, was
Dermal Tissue
Dermal
Tissue
doestissues
tissue
culture
How
doesform
tissue
the process by whichHow
embryonic
develop
their work?
special
and culture
Explain the following terms: translocation, transpiration, transpiration
Usually the initial tissue sample isUsually
minced,the
and
initial
thentissue
digested
sample
withisanmin
name suggests,
Connective
connects,
tissue –binds
as theorname
separates
suggests, connects, binds or separates
function.
In
studying
twoand
four-cell
frog
embryos
he
found
that
stream.
Name the principal tissue involved in (i) translocation, (ii) the
enzyme such as trypsin to remove
enzyme
the extracellular
such as trypsin
matrix to
that
remove
holds th
ood and bone.
tissues and organs e.g. blood and bone.
some kinds of cell differentiation
were
dependent
on
factors
external
to
transpiration stream.
the cells together. After that, the cells
the cells
are free
together.
floating,
After
and
that,
extracted
the cells
Fig.2 Outline of plant tissue
Fig.2 Outline of plant tissue
d groupsMuscle
of cellstissue
that can
– specialised
contract and
groups
exert of
a cells that can contract and exert a
the cell, such as its location
in
the
early
embryo,
while
other
changes
using centrifugation.
using centrifugation.
hree type
pulling
of muscle
force.tissue:
There smooth
are three
muscle,
type of muscle tissue: smooth muscle,
were controlled from Cells
within
arethe
thencell.
implanted or ‘seeded’Cells
into are
an artifi
thencial
implanted
structure
oror
‘seeded’
scaffoldinto
cells that
Epithelial
cover organ
tissue surfaces
– layers of
such
cells
asthat
the cover organ surfaces such as the
the inner
surface
lining
of ofthetheskin
digestive
or the
tract.
inner
lining of
the digestive tract.
2001
Leaving
Certifi
cate
Higher
Level
protection,
Epithelial
secretion,
tissues
andserve
absorption.
for protection, secretion, and absorption.
r linings2005
which
of organs;
isLeaving
found
skeletal
in the
muscle,
inner linings
which
organs;
skeletal
muscle, which is
Certifi
cateisofOrdinary
Level
The
Skin
The Skin
that is capable of supporting a three-dimensional
that is capabletissue.
of supporting a three-dim
ones andattached
facilitates
to movement;
articulated bones
and cardiac
and facilitates movement; and cardiac
1885
Roux
a of
portion
the medullary plate of a chicken
The
skin
is
the
body’s largestsection
organ.
The
It of
skin
is made
upbody’s
of In
layers
largest
of epithelial
organ. removed
It is made up
layers ofof
epithelial
Which
of
the
two
diagrams
1
or
2
represents
a transverse
ais the
of the heart.
muscle – the muscle tissue of the heart.
If cultured
tissuessaline
are to be
used for
If for
cultured
tissue
reconstruction,
tissues
are to
the
be scaffolds
used for tis
embryo
and
kept
it
alive
in
a
warm
solution
several
days;
this
tissues.
tissues.
young root?
must be biocompatible; it is also desirable
bethat
biocompatible;
they be absorbed
it is also
bydesira
the
ming the
Nervous
brain, spinal
tissue –cord
cellsand
forming
peripheral
the brain, spinal cord and peripheral
indicated
that
it might
be possible
toacts
culture
cellsmust
in vitro.
The
skin
consists
of
three
primary
layers:
The
skin
the
consists
epidermis,
of
three
which
primary
acts
as
layers:
a
the
epidermis,
which
as
a
surrounding tissues and not require surrounding
surgical removal.
tissues
The
and
scaffold
not require
should
surg
of neurons,
nervous
which
system.
transmit
consists
electricalofimpulses
neurons,
electrical impulses
(i)
State
twoIt features
of the which transmit
barrier
to
moisture
and
infection;
the
barrier
dermis,
to
moisture
which
cushions
and
infection;
the
body
the
dermis,
which
cushions
the
body
degrade at roughly the same rate asdegrade
the newat
tissue
roughly
develops.
the same rate as the
non-neuronal
and neuroglia,
cells that which
aid and
are
participate
non-neuronal
in cells that aid and participate in
Jacques
Louis
Reverdin
(1842–1929)
diagram
that
indicate
it
is
a
from
stress
and
strain
and
contains
from
the
stress
nails,
and
hair
strain
follicles,
and
sebaceous
contains
the
nails,
hair
follicles,
sebaceous
s aroundthe
therapid
body.transfer of signals around the body.
glands etc; and the hypodermis (also
glands
called
etc;the
andsubcutaneous
the hypodermis
tissue),
(also called the subcutaneous tissue),
root.
What
are
the
applications
What
ofare
tissue
the application
culture?
Jacques
Louis Reverdin
was
born
invariations
Switzerland
in
1842.
He
completed
which acts as insulation and protects
which
the acts
internal
as insulation
organs
from
andvariations
protects
the internal
organs
from
of the
important
therapeutic
of the most
of
important
tissue
culture
therapeutic
is in a
in temperature.
in temperature.
his medical studies inOne
Paris
in most
1865.
He worked
asOne
a applications
doctor
in Paris
and
(ii) The letters A, B, C in the
skin grafting
for
with serious
skin
burns.
grafting
Burns
for
are
patients
traditionally
with serious
treatedbur
later
in
Guyon
1869,
hepatients
developed
a technique
for
grafting
diagram represent three
As one of the body’s major organs,As
theone
skinofhas
the abody’s
signifi
cant
major
role
organs,
to play
thewhere,
skin hasin
a signifi
cant
role
to play
by taking a thin layer of skin fromby
antaking
undamaged
a thin layer
area of
known
skin as
from
thean
pieces
skin
onto
open wounds,
allowing them
tocases
heal.
As
newson burn
in homeostasis – the maintenance ofinthe
homeostasis
internal environment
– thesmall
maintenance
of
the body
ofof
the
internal
environment
of the body
different tissue types. State
donor site, and placing it on burn area.
donorInsite,
andofplacing
severeitburns
there
area
in
a
suitable
state
for
effi
cient
tissue
in
cell
a
suitable
metabolism.
state
It
for
plays
effi
cient
an
important
tissue
cell
metabolism.
It
plays
an
important
of the treatment spread
used sites.
the technique.
which tissue type in the
mayothers
be few donor
Skin graftsmay
frombeother
few donor
peoplesites.
– allografts
Skin grafts
– canfrom
role in temperature regulation and isrole
alsoinpartly
temperature
responsible
regulation
for protecting
and is also partly responsible for protecting
be used as temporary dressings, but
beare
used
eventually
as temporary
rejected.
dressings, but ar
following list is represented
the body against pathogens. Whenthe
thebody
skin is
against
damaged
pathogens.
When
cuts or
the
skin is damagedthe
through
cuts or of wounds by helping to
Histhrough
methods
revolutionised
treatment
by each letter: ground tissue, vascular
tissue,
dermal istissue.
the mid-1970s,
researchers
In the mid-1970s,
University discovered
researchers
at Harvar
they
burns the
risk of infection
greatlyburns
increased.
the risk
Skin
of infection
tissue that
is has
greatly
been
increased.InSkin
tissue that has
been at Harvard
prevent infection and accelerating the healing process. However the that
CONNECTIVE
EPITHELIAL TISSUE
TISSUE
EPITHELIAL TISSUE
could
achieveasgrowth
couldofachieve
dermalgrowth
cells inand
vitroproliferation
in order
damaged beyond repair must be removed
damagedand
beyond
replaced
repairasmust
quickly
be removed
as
and
replaced
quicklyand
as proliferation
grafts
were
not permanent.
(iii) Name two vascular tissues and give
onebyway
in which
they layer
differ.
to produce
a keratinising,
to produce
skin epithelium.
a keratinising,
Keratin
transplantab
is the
possible
a suitable
protective
possible
until such
by a time
suitable
as
new
protective
skin
grows
layer
until such
time as new
skin growstransplantable
tough, insoluble
tough, ininsoluble
skin, hair
fibrous
and nails.
proteinIt foun
is
or is cultured and surgically graftedortoisthe
cultured
underlying
and surgically
tissue. grafted to the underlying
tissue. fibrous protein found
(iv) State a function of ground tissue.
the structural matrix of keratin in the
the structural
epidermismatrix
that makes
of keratin
the in
skin
the
The epidermis provides a relativelyThe
dryepidermis
and impermeable
provides
barrier
a relatively
to fluiddry and
impermeable
barrier to fluid
Ross
Granville
Harrison
(1870–1959)
almost waterproof.
almost waterproof.
loss. Loss of this function in burnsloss.
contributes
Loss ofto
this
thefunction
massiveinflburns
uid loss
contributes to the massive fluid loss
Harrison was an American
biologist
and
anatomist
anda researchers
one
of the
The Harvard
researchers
were
ableThe
to expand
Harvard
small sample
were
of skin
abletoto e
and consequent dehydration.
and consequent dehydration.
2006 Junior Certificate Science
leading embryologistover
in the
early
twentieth
century.
special
interest
10,000
times
its original
size over
in aHis
short
10,000
time,
times
making
its original
the process
size in a
Explain the term tissue.
Hair Folicle
Hair Folicle
valuable
patients suffering
from severe,
valuable
third
for patients
degree
burns,
suffering
fromthe
seve
was in the development
of for
amphibian
embryos,
especially
those
ofwhere
MUSCLE
NERVOUS
TISSUE
TISSUE
NERVOUS TISSUE
for skinthe
grafting
is low.
potential for skingroups
grafting of
is low.
salamanders, and he potential
investigated
effects
of transplanting
BURN
BU RN
3˚
3˚
Onion epidermis is a tissue only one cell D thick.
It is used in school D E PTH
EPTH
laboratories on microscope slides to investigate
plant cell structure 1˚
1˚
d into three
Plant
broad
tissues
cantypes,
be divided
which
into
together
three how
broadto
tissue
types, a
which
together slide from a
using
a tissue
microscope.
Describe
prepare
microscope
mass. plant
are often
referred to as biomass.
tissue.
sues foundFig.
In humans
1 Four main types of tissues found In humans
ost layerDermal
of cellstissue
forming
– the
theoutermost
outer surface
layerofof cells forming the outer surface of
g plant body.
the leaves and of the young plant body.
For further examples of past paper questions check www.sta.ie
s of cells
Vascular
that transport
tissue – flconsists
uid and nutrients
of cells that transport fluid
3˚ and nutrients
ary components
within the
of plant.
vascular
Thetissue
primary
arecomponents
xylem
of vascular tissue are xylem
4˚
and phloem.
Did You Know?
3˚
4˚
SKIN LAYE R
SKIN LAYE R
work over
theembryo
past thirtyto
years
Further work
the past
thirty years
cells and tissues fromFurther
one part
of an
another.
Heover
used
dyes
Epidermis
has ledand
toEpidermis
advances
in theofcell
growth
has ledthe
to advances
in the
cell growth
to follow the development
migration
cells
within
embryo;
this
process, reducing the amount of time
process, reducing the amount of time
made it possible to track
and
map
the
way
various
tissues
and
organs
it takes to culture the skin, while
it takes to culture the skin, while
Dermis
Dermis
develop.
To facilitateincreasing
his research
he and
devised
methodstheofamount
culturing
the amount
size of the
increasing
and size of the
grafts available. Because these
grafts available. Because these
amphibian cells in vitro.
Subcutaneous
Layer
Read more
Muscle
are autologous
cells (the patient’s
are autologous cells (the patient’s
Subcutaneous
Layer the risk of
own cells),
rejection
own cells), the risk of rejection
about
authors
onpathogen
www.sta.ie
and other
pathogen
transmission
with
and
transmission with
Musclefamous
autografts is low.
autografts is low.
hose primary
Ground function
tissue – istissue
the manufacture
whose primary function is the manufacture
nthesis; ofit nutrients
can also by
andphotosynthesis;
store nutrients.it can also and store nutrients.
Sweat Gland
Sweat Gland
from the
Ground
meristem
tissue
and
develops
consists
from
of the
anddeaths
consistsof of
the
In
the
USA
burning
accounts
formeristem
over 4%
children
under
oneSkin showing levels of burning
Fig.3of Skin
showing levels
of burning
Fig.3
and sclerenchyma
parenchyma,
cells.
collenchyma and sclerenchyma cells.
year of age and 16% of deaths of those aged between one and four years.
Studies in Ireland indicate that 90% of burn accidents occur in the home
– usually in the presence of an adult. Although typically about 98% of
victims survive, many are permanently affected.
Prior to the development of skin grafting, burns covering half the body
surface were typically fatal. Today people with even more extensive burns
can survive.
In Ireland incidence of serious sunburn injuries is exceptionally high –
especially for babies. Despite awareness campaigns, it appears that
parents are often do not realise the immediate danger of such burns and
the consequent increased risk of skin cancer in later life.
Apart from suffering damage to the skin burn victims often suffer from
smoke inhalation, cuts, blood loss and broken limbs. In order to recover
from such trauma multiple treatments must be provided together.
Maintaining proper nutrition in such circumstances has also been shown
to be critically important.
This process is known as cultured
This process is known as cultured
epithelial autograft (CEA) and is used
epithelial autograft (CEA) and is used
on patients who have burns covering
on patients
whograft
have burns covering
Fig.4 Skin
more than 30% of their bodies.
more than 30% of their bodies.
Revise The Terms
Can you recall the meaning of the following terms?
Reviewing the terminology is a powerful aid for recall
and retention.
Tissue; organ; pathogen; epidermis; dermis; hypodermis; homeostasis;
tissue cell metabolism; impermeable; Tissue culture; growth media; in
vitro; organ culture; cell culture; explant culture; plant tissue culture;
Tissue engineering; stem cell research; enzyme; trypsin; extracellular
matrix; centrifugation; implanted; tissue reconstruction; biocompatible;
biodegradability; osmotic pressure; culture conditions; transplanted;
skin grafting; donor site; allografts; proliferation; keratin; keratinisation;
keratinocyte; fibrous protein; stratus corneum; autologous; autografts;
cultured epithelial autograft; cartilage; chondrocytes; autologous
chondrocyte implantation.
Check the Glossary of Terms for this lesson at www.sta.ie