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hapter 2 : Support And
Locomotion
hapter 2 : Support And
Locomotion
2.1 Understanding Support
And Locomotion In Humans
And Animals
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Necessity For Support And Locomotion In HumaAnd Animals
Locomotion is the movementof wholeorganisms from place to place
Humans and animals need to move fromplace to place:
a. For foodb. For shelter
c. To nd mate for reproductiond. To escape from predators (protectione. To nd prey
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ems That "ould #e Faced #y Humans And AnimaSupport And $ovement
Movement in water : Water is denseand canresist movement
Movement in air : A lot of eort is required by an
animal to overcome the force of%ravity
Movement on land : Soft and collapsible bodytissues cause
instability
!hese problems can be overcome by having as&eletal system.
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The Functions 'f S&eletons
!o provide shape for body and support for
organism
"or muscle attachment# to enable movement
!o protect internal organs from in$ury
!o store certain minerals such as calcium and
phosphorus %bone&
!o produce blood cells %bone marrow&
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Types 'f S&eleton In Animals
) Hydrostatic s&eleton
'onsists of internal watery (uids containedwithin con)ned spaces in the body
!his (uid is held under pressure incompartments surrounded by muscles
Since the (uid cannot escape# it forms anincompressible s*eleton
+g +arthworth# $elly )sh
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Types 'f S&eleton In Animals
* +,os&eleton
An outer covering which is made up of rigid andstrong materials such as calcium or chitin
!he cuticle of an insect covers the surface of its
body !his cuticle is covered with wa, to preventwater loss
+,os*eletons are non-living structures# incapableof growth .n order to grow# arthropods have to
shed their s*eletons through ecdysis %moulting&
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Types 'f S&eleton In Animals
+ndos&eleton
.nternal s*eletoncomprising of manycomponent parts ofcartilage or bones
to which musclesare attached
/ertebrates depend
on the bones forlocomotion
+g 0irds# crocodile#Human
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"hapter * Locomotion And Suppo
Structure 'f The Human S&eleton
() A,ial s&eleton (* Appendicular s&eleton
S&ull
-ertebral column(spine
ib ca%e(rib bones/
sternum
!ectoral %irdle(scapula/ clavicle
0pper limbs
(humerus/ radius/ulna/ hand
!elvic %irdle
Lo1er limbs(femur/ tibia/
bula and tarsals
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'arpalsMetacarpals
1halanges
!arsalsMetatarsals1halanges
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"hapter * Locomotion And Suppo(a The s&ull (**bones
nasal
ma,illa
mandibleli%ament
"ranium (cranial bones 2 eight (at boneswhich become fused soon after birth 2 encloseand protect the brain
facial bones - fourteen bones 2 protect andprovide the entrances to the digestive andrespiratory systems
consists of
hyoid
Suture 2
immovable $ointsthat held thebones together
!he lo1er 3a1is the only freelymoveable boneof the s*ull
(b Th - t b l
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"hapter * Locomotion And Suppo(b The -ertebral"olumn (
!he vertebralcolumn also *nownas the bac&boneor spine!here are discs ofcartila%e betweenad$acent vertebrae#
*nown asintervertebraldisc# which acts as:
a& shoc* absorbingcushion
b& reduces frictionbetween vertebrae
c& allows movementbetween ad$acentvertebrae
4 nec& orcervical vertebrae
)* thoracic vertebrae
5 lumbar vertebrae
5 sacral (sacrumvertebrae
Trian%ular bones6 caudal vertebral 1hichfused to%ether to form
Intervertebrdisc
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"hapter * Locomotion And Suppo
The "ommon "haracteristics 'f A Typical -ertebra
efer te,tboo& p% 5)/ Fi%. *.6
There are variations in the si7e and
shape of the vertebrae #ut a typical vertebra has 8 a solid body or centrum a neural canal and several bony processes
"h * L i A d S
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"hapter * Locomotion And Suppo
The "ommon "haracteristics 'f A Typical -ertebra
$uscular attachment
!rotects the spinal cord
$uscularattachment
Attachment 1ith
the ne,t vertebra
Spinal cord
passes throu%hthis canal It is continuous1ith the neuralcanals of othervertebrae
Neural spine9 spinous process
Neural arch
Transverseprocess
"entrum (body is asolid piece of bonethat can resistcompression
ural canal9 vertebral foramen
7y%apophyses 9 articular process
"h t * L ti A d S
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!he $oint between the s*ull and the atlas allowsthe head to move up and down
"hapter * Locomotion And Suppo
The First "ervical -ertebrae 2 Atlas!here are seven cervical vertebra !he )rst is*nown as atlas
!he )rst cervical vertebra is the atlas!he atlas is aring2shapedbone with largefacets toarticulate withthe base of thes*ull %occipitalcondyle&.t has a large
neural canal#no centrum anda small neuralspine
Neural spine
Neural canal
Li%ament
"avity forodontoidprocess
-ertebrarterial canal9tranverseforemanTransverse
process
Facet for
articulatin%1ithoccipitalcondyleAnterior -ie1
"h t * L ti A d S
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.t allows the atlas to turn about the adenoid process
!he 'entrum e,tendsupwards to form the
adenoid process
ITeach Biology Form 5
"hapter * Locomotion And Suppo
The Second "ervical -ertebrae 2 A,is
!he second
cervical vertebrais the a,is
.t has a "entrumand transverseprocess
Which )ts into the lower part of the neural canal ofthe atlas
neural spine
post7y%apophyses
transverse
process"entrum
adenoid processvertebrarterialcanal
neural canal
Anterior -ie1
"hapter * Locomotion And Suppo
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Has two vertebrarterial canals through the
artery and nerve pass throughITeach Biology Form 5
"hapter * Locomotion And Suppo
The Third To The Seventh "ervical -ertebra
!he smallest and lightest vertebrae
neural spineneural arch
neural canal
"entrum-ertebrarterialcanal
Transverseprocess
pre7y%apophysis
Anterior -ie1
"hapter * Locomotion And Suppo
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"hapter * Locomotion And Suppo
The Thoracic -ertebra
There are )* thoracic vertebrae
A thoracic vertebra has a "entrum/ a circularneural canal/ a lon% neural spine 1hich point
do1n1ards/ t1o transverse processes.The neural spine and transverse processes arefor the attachment of muscles and li%aments.
Facets on both sides of the "entrum/ and at
the ends of the transverse process are for
neural spine(muscle attachment
transverse processarticulates 1ith rib
surface for articulation 1ithne,t vertebra
"entrum
neural canal throu%h 1hichspinal cord passes
Anterior -ie1
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"hapter * Locomotion And Suppo
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"hapter * Locomotion And Suppo
The Typical Lumbar -ertebra
neural spine
$etapophysispre7y%apophysis
Transverseprocess
"entrum
hypapophysis
post7y%apophysis
anapophysics
Anterior -ie1 Side -ie1
Are the bi%%est vertebrae in the vertebral column.
ey have short but bi% centrum because they are sub3the %reatest stress
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Lumbar /ertebrae %3&
!osition 8 1aist
The lar%est andstron%est in thevertebral column.
2 small neural canal.
2 short neural spine.
2 thic& and lar%ecentrum
1hich bear the1ei%ht of
the lo1er bac&.
2 lon% transverseprocesses for muscle
attachment.
"hapter * Locomotion And Suppo
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"hapter * Locomotion And Suppo
Attachment 'f 'ne Lumbar -ertebra To Another
Anterior -ie1
"hapter * Locomotion And Suppo
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"hapter * Locomotion And Suppo
Attachment 'f 'ne Lumbar -ertebra To Another
Side -ie1
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Sacrum : "occy,
Sacrum (5)
- position : pelvic
region
- fused to each other.
- has 4 pairs of
opening.
- triangular shape.
Coccyx (4)
- caudal region.
- ones fused to
each other !hich
tapers at one end.
"hapter * Locomotion And Suppo( Th ib
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ITeach Biology Form 5
"hapter * Locomotion And Suppo( The ib
"a%e
!here are 45 pairs of
ribs in the s*eleton ofman
-ertebral column
Sternum
Floatin% ribs
!he )rst 6 pairs areconnected directly to
the sternum and arecalled true ribs
!he ne,t 7 pairs areattached to the 6thpair
and are called falseribs
!he last 5 pairs are(oating ribs
"hapter * Locomotion And Suppo
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"hapter * Locomotion And Suppo
) The !ectoral ;irdle
"lavicle
Scapula
Head
Shaft of humerus
Articulatin% surface
!he pectoral girdle is aframewor* of bone
consisting of two similarhalves $oined in the mid2ventral line
+ach half consists of twobones
2 the scapula and2 the clavicle
!he scapula or shoulderblade is large# (at and
triangular
!he clavicle or collar bone isslender and curved slightly
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p pp
!he pelvic girdle consistsof two similar halves
which $oin the sacrum atthe bac* and meet at thepubic symphysis in front
+ach half of the pelvic
girdle consists of threebones2 the ilium#2 the ischium and2 the pubis
!he head of the femur)ts into the acetabulum
* The !elvic ;irdle
!ubic symphysis
Sacrum
llium
Acetabulum
"occy,
Ischium
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0pper limb
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6 Hind limb
"hapter * Locomotion And Suppoole of 3oint s&eletal muscle
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ITeach Biology Form 5
p ppole of 3oint/ s&eletal muscle /tendon and li%ament in
$ovement
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ITeach Biology Form 5
$ovement And Support
Structure 'f A
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"hapter * Locomotion And Suppo
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ITeach Biology Form 5
0nderstandin% Support And Locomotion In Humans And Ani
ole 'f Li%ament In $ovement
Li%ament
Ligaments connect bone to bone
'onsists of tough# elastic )bers
"hapter * Locomotion And Suppo
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0nderstandin% Support And Locomotion In Humans And Ani
oles 'f Tendons In$ovement
Tendons
'onnect muscles to bones
'onsists of tough# inelastic collagen )bers
"hapter * Locomotion And Suppo
l 'f $ l I
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ITeach Biology Form 5
ole 'f $uscles In$ovement
$uscles
Muscles which are attached to bones are calleds*eletal %striated& muscles
S*eletal muscles are arranged in pairs calledantagonistic pairs When one muscle contracts#the other muscle rela,es
"hapter * Locomotion And Suppo
Structure And "ontraction 'f S&eletal
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S uc u e d "o ac o ' S e e a$uscle
A muscle is made up of many long cylindrical cellscalled muscle )bers
+ach muscle )ber is made up of a bundle of smaller)bers called myo)brilsA myo)bril has a distinctive banding pattern due tomicro)laments
!here are two types# thic* %myosin& and thin %actin&
micro)laments
!he thic* )laments are con)ned to the dar* bands#made up of myosin
!he thin )laments occur in the light bands# and e,tend
beyond the thic* )laments# composed of the protein#actin
!he )laments are the contractive apparatus ofmuscles
When the muscle contracts# the thin )laments slide
along the thic* )laments
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"hapter * Locomotion And Suppo
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ITeach Biology Form 5
$ovement In Strai%htenin% The Arms
!he triceps
musclecontracts/ thebiceps musclerela,es 8lna ispulled do1n
!he triceps andbiceps musclesare described asanta%onistic
muscles.
scapula
#all andsoc&et 3oint
#iceps
musclerela,es
Triceps musclecontracts
0lna
Tendon
adius
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$ovement In #endin% The Arms
!he biceps muscle
contracts# the tricepsmuscle rela,es 8lnais pulled up
!he biceps muscle
which causes bendingwhen it contracts isreferred to as the=e,or while the
triceps muscle whichcauses straighteningwhen it contracts isreferred to as thee,tensor
Triceps$usclerela,es
#iceps musclecontracts
"hapter * Locomotion And Suppo
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F
$ovement In The Lo1er Limb
) Strai%htenin% the le%8) ;luteus ma,imus (the lar%est and supercial muscle of
the hips contracts/ pulls the femur bac&1ard The >uadriceps femoris contracts/ the biceps femorisrela,es/ pulls the tibia and bula for1ard. The le% isstrai%htened.
;luteus ma,imus
?uadriceps femoriscontractsfemur
Tibia and bula
#iceps femorisrela,es
"alf musclecontracts
* #endin% the le%8 The >uadriceps femoris rela,es/ the biceps femoris
(hamstrin% muscle contracts. The le% is bent
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The $uscle Involves In @al&in%
The calf muscle contracts and raises the heel. In doin%so/ it e,erts a for1ard thrust by pushin% the ball of thefoot a%ainst the %round.
The hamstrin% muscle (biceps femoris contracts to pullthe femur bac& and bends the &nee. The le% is raised.
femur
F
;luteus ma,imus
?uadriceps femoriscontracts
Tibia and bula
#iceps femorisrela,es
"alf musclecontracts
As the ri%ht foot loses contact 1ith the %round/ the1ei%ht of the body is no1 supported by the left le%
1hich is still contact 1ith the %round.
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The $uscle Involves In @al&in%
Ne,t/ the >uadriceps femoris muscle contracts/ pull thefemur for1ard and e,tends the le%.
@hen the e,tension of the le% is completed/ the tibialiscontracts to lo1er the heel. The foot the re%ainscontact 1ith the %round 1ith the heel taouchin% the%round rst. The 1ei%ht of the body is no1 supportedon the ri%ht le%.
femur
F
;luteus ma,imus
?uadriceps femoriscontracts
Tibia and bula
#iceps femorisrela,es
"alf musclecontracts
The 1hole se>uence is repeated 1ith the left le%.
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"hapter * Locomotion And Suppo
Locomotion In Animals
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(p% B #e%innin% from the anterior/ the circularmuscles contract/ the lon%itudinal muscle rela,/chaetae (bristles retract causin% the earth1orm
become thinner and lon%er and anterior se%mentse,tend for1ards.
(p% ) Then/ the lon%itudinal muscles contract/ thecircular muscles rela,. "haetae anchor the shortenedse%ment on the %round.
The earth1orm becomes shorter and thic&er (bul%e.
ITeach Biology Form 5
Locomotion In Animals
motion in an earth1orm 2 Animals 1ith a hydrostatic s&eleton The force of contraction is
applied to a =uid2lled
cavity 8 caelom The caelom is surrounded
by t1o anta%onistic layersof muscle
(i the circular muscle C
surround the chamber (ii the lon%itudinal
muscle C e,tend from oneend to the other (p% )
posterior anterior
"hapter * Locomotion And Suppo
Locomotion In Ani
mals
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The shortened se%ment in the posterior is pulledfor1ard.
@ith the anterior se%ments remainin% stationary/the peristaltic 1ave of contraction of thelon%itudinal muscles continues do1n the posterior/pullin% the rear se%ments for1ard.
ITeach Biology Form 5
Locomotion In Animals
motion in an earth1orm 2 Animals 1ith a hydrostatic s&eleton
posterior anterior
"hapter * Locomotion And Suppo
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ITeach Biology Form 5
Locomotion In Animals
comotion in a %rasshopper C animal 1ith an e,os&el
Locomotion in%rasshopper is
by 1al&in%/3umpin% and
=yin%.
@al&in%
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"hapter * Locomotion And Suppo
Locomotion In Animals
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ITeach Biology Form 5
Locomotion In Animals
c Locomotion in a fro% 2 endos&eleton
!he strong hind legs are folded in the shapeof 9;!he hind legs straighten!he fore limbs move forward ready to land.t lands with its fore limbs
The mechanism of 3umpin%
"hapter * Locomotion And Suppo
ti I A Fi h Ad t ti 'f Fi h T $ I
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Streamlined body
Its body is broad at the anterior andtapers to the tail/ enables the sh to movethrou%h 1ater 1ith minimum resistance.Dp% * (aEScales
The bac&1ard/ directed/ overlappin% scalesand covered by a slimy coatin% to reduceresistance 1hen s1immin%.
S1im bladder p% (c
A s1im bladder is a %as lled sac insidethe abdomen of the sh.
#y controllin% the amount of %as in thebladder/ the sh can chan%e itsbuoyancy to reach certain depth in the1ater.
ocomotion In A Fish 2 Adaptations 'f Fish To $ove In
"hapter * Locomotion And Suppo
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Fins
Fins are necessary for stability andprecisely control movements throu%h the1ater
The pectoral and pelvic ns (paired nsare used for steerin% and bra&in%
The dorsal and ventral n (median nsincreases the vertical surface of the shand &eeps it upri%ht by preventin% it from
rollin% side1ays. The caudal or tail n %enerates thefor1ard force 1hich propels a sh for1ardand aids in steerin%
comotion In A Fish 2 Adaptations 'f Fish To $ove In
Three &inds of instability
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"hapter * Locomotion And Suppo
o
motion In A Fish 2 Adaptations 'f Fish To $ove In
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Alternate contraction and rela,ation ofmyotomes causes the body to bend side toside and the tail to beat and producesfor1ard thrust.
ITeach Biology Form 5
Arran%ement 'f $yotomesIn Fish
vertebrae
myotomes(muscle bloc&s
"onsist of muscle bloc&s or myotomes (@
shaped arran%ed on both sides of thevertebral column (bac&bone@ shaped myotomes
p
"hapter * Locomotion And Suppo
$echanism 'f Locomotion In Fish
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$echanism 'f Locomotion In Fish
$uscleson leftside rela,
$uscleson ri%htsidecontract
and pullthe tail tothe ri%ht
For1ard thrust
Side1ays thrust
Thrust of 1ater
$uscles onleft side
contractand pullthe tail tothe left
$uscles on
ri%ht siderela,
Thrust of 1ater
For1ardthrust
Side1ays thrust
Fish moves to the left/ tail pulls to the ri%
Fish moves to the ri%ht/ tail pulls to the l
"hapter * Locomotion And Suppo
(e
Locomotion In A #ird
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(
Lo1 body 1ei%ht# which reduces energy required in(ight !he s&ull is thin# it has no teeth and the lon%bones are hollo1
lift
%ravity
Air =o1
aptations For Fli%ht In A #ird
"ore-limbs are modi)ed as wings
Wings are aerofoils which have a conve, uppersurface and a concave lower surface
!he shape generates lift when it movesthrough air
aerofoil
Slo1er air =o1 at the
bottom causes hi%hpressure
Faster air =o1 at thetop causes lo1pressure
!he body is covered in feathers# which provides
insulation against heat loss =not involved in (ying
Locomotion In A #ird 2 0p1ard $ovement 'f The
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@in% urin% Fli%ht
1age >? !he pectoralis minor contractsand pectoralis ma$or rela,es# pulls thehumerus over the coracoid bone !he
wings are pulled up
!he (ight feathers twist open and air(ows through the gaps between them
Air =o1
Sternum
!ectoralis minor
"oracoid
Humerus
adius0lna
!ectoralis ma3or
Locomotion In A #ird 2 o1n1ard $ovement 'f The
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@in% urin% Fli%ht
.n the downward movement of the wing#
As both wings go down# air resistance
closes the (ight feathers# pushing the fullwing areas on the air and lifting the birdup
Air =o1
Sternum
!ectoralis minor
"oracoid
Humerus
adius0lna
!ectoralis ma3or
- the pectoralis ma$or contracts#- the pectoralis minor rela,es and pulls thewings down
!he wings which move up and downrhythmically generate the forward thrustas well as to provide the lift for the (yingbird
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hapter 2 : Support And
Locomotion
hapter 2 : Support And
Locomotion
2.2 Appreciating A HealthyMusculoskeletal System
"hapter * Locomotion And Suppo
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Impaired$usculos
&eletalSystem
$uscle"ramp
$uscularystrophy
'steoporosis
Arthritis
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@steoarthritis
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@steoarthritis
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heumatoid arthritis
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heumatoid arthritis
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Bout
A i ti A H lth $ l & l t l S t
"hapter * Locomotion And Suppo
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Appreciatin% A Healthy $usculos&eletal System
$aintainin% A
Healthy$usculos
&eletalSystem
#alanced diet ;ood !osture
!roper AttireFor ailyActivities
Ade>uate+,ercise
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hapter 2 : Support And
Locomotion
hapter 2 : Support And
Locomotion
2.3 Understanding SupportIn Plants
Cecessity of Support in
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1lants4 "or upri%ht position so that their leaves are
positioned in such a ways as to ma,imise theabsorption of sunli%ht for photosynthesis.
5 "lowers need to lifted for pollinationwhile fruitsand seeds are held at high position for dispersion
7 1rovide stren%thto withstand wind resistance
? Support in plants is mainly provided by the turgidity
of cellsand the distribution of vascular bundlesnamely the ,ylem vessels and cellulose in the cell
walls
Support In A>uatic
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!lantsa Submer%ed plant
+g: Hydrillasp
have very thin # narrow andvery (e,ible leaves
!his type of leaves provideslittle resistance to water (ow
!his means that submergedplants can be tugged at andpulled by water currents withlittle damage
Support In A>uatic
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pp >!lantsa Submer%ed plant
!here are air sac or airspaces within the leaves andstems which *eep the plantsa(oat close to the surface to
obtain ma,imum light Since 1ater buoyancy
provides support for theseplants# their stem have no
1oody tissue !herefore# if these plants are
removed from water# theybecome limp and (oppy
Support In A>uatic
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pp >!lantsb Floatin% plants Supported by the upward
thrust provided by thesurrounding water
!hey have aerenchymatissue and air sac in theroots# stems and leaves forsupport and to enable themto (oat
+g water hyacinth
efer te,t boo* page >?#"igure 56
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Support in aquatic plants
Aerenchyma tissues
Are spongy tissues withlarge air spaces betweenthe cells %intercellular airspaces&
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Support in terrestrial plants
!he type of terrestrial plant such as:
a woody plantsb herbaceous plants
c creepers# vines and lianas %woodyvines&
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a Woody plants
In youn% plants/ thesupport is provided by thetur%idity of the cellsandthe cellulose cell 1alls.
In older plants/ thesupport is provided byli%nied ,ylem vessels/tracheids and
sclerenchyma tissues.
a Woody plants
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a Woody plants
a Gylem vessels do not have cytoplasm in
them.
They are lon% cylindricalstructures placed end toend to conduct 1ater fromthe root to the leaves.
They have thic& 1alls ofli%nin 1hich are depositeddurin% the plant secondary%ro1th.
This results in the
a Woody plants
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a Woody plants
ierent types ofvessels8
Annular or rin%2shapedvessels
Spiral vessels
Scalariform or ladder2li&evessels
pitted vessels
a Woody plants
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a Woody plants
The formation of thesetypes of vessels iscollectively &no1n as theprimary ,ylem.
As plant %ro1/ they usuallyunder%o secondary %ro1th1hich results in theformation of a lar%eamount of secondary
,ylemcalled 1ood
a Woody plants
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a Woody plants
b Tracheids Are dead cells 1ith thic&
1alls but 1ith a very smalldiameter.
They are found 1ith ,ylemvessels and to%ether they%ive support to the plant.
a Woody plants
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a Woody plants
c Scelerenchymatissues8
They are thic&/ ri%id andnon2stretcheable cell
1alls.
o not allo1 1ater to %otrou%h.
Sclerenchyma tissuessupport the non %ro1in%parts of plants.
a Woody plants
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a Woody plants
T1o types ofsclerencyma tissue8
A. Sclerenchyma bresare
lon% / strai%ht and thincells found around thevascular
bundles/ providin%support.
#. Sclereids are small/short/ circular/ irre%ularlyshaped cells 1ith li%nied1alls 1hich harden theouter layer of the seeds.
b Herbaceous plants
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b Herbaceous plants Support is provided by the
tur%idity of parenchyma andcollenchyma cells and ,ylemtissues
When the parenchyma cells are
)lled with water# they becometur%idand press against eachother to maintain the shape and)rmness of the plant
'ollenchyma cells haveunevenly thic*ed cellulose andthe midrib of the leaves providemechanical stren%th.
'reepers /ines and Lianas
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'reepers# /ines and Lianas
1lants with modi)cations to obtain supportasthey are not able to support themselvesupright
+,amples of structural modi)cations:
4&!endrils
5& Modi)ed roots
7& Modi)ed shoot
?&!horns
'reepers
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'reepers
The cucumber plant Tendrilsare slender# coiled structures found on the stemswhich twine themselves around a support to help
a plant "unction : to support its weight and climb
easily
Gloriosa sp Tendrilsat the end of the leaves "or climbing +nable the plant to obtain support
'reepers
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'reepersThe pepper plant
has modi)ed rootsto twine around anob$ect
"unction: for support
$ornin% %lory and lon% bean plant Shootswhich are able to twine around an
ob$ect# "unction : to support itself
ose bush have thorns "unction : to hoo* on to a nearby support
Lianas
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Lianas
+,ample8 attan
8sed in ma*ing furniture and ropes
Have variety of adaptations to attachthemselves to their host such as twiningstems and thorns
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Thank you.