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hapter 2 : Support And

Locomotion


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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* +,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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+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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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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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


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


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


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Has two vertebrarterial canals through the

artery and nerve pass throughITeach Biology Form 5


The Third To The Seventh "ervical -ertebra

!he smallest and lightest vertebrae

neural spineneural arch

neural canal

"entrum-ertebrarterialcanal

Transverseprocess

pre7y%apophysis

Anterior -ie1


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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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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.


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Attachment 'f 'ne Lumbar -ertebra To Another

Anterior -ie1


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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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"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


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) 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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p ppole of 3oint/ s&eletal muscle /tendon and li%ament in

$ovement

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$ovement And Support

Structure 'f A

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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


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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


l 'f $ l I

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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


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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$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


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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



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



The 1hole se>uence is repeated 1ith the left le%.

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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.



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


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.



motion in an earth1orm 2 Animals 1ith a hydrostatic s&eleton

posterior anterior


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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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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%


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


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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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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.


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


$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


(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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Locomotion


Locomotion

2.2 Appreciating A HealthyMusculoskeletal System


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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


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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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Locomotion


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.

chapter 2 f5

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