Biology Form 5 Chapter 2 - Locomotion & Support : 2.1 Part 3

1. BIOLOGY FORM 5
CHAPTER 2
LOCOMOTION & SUPPORT
PART 3

2. LLOOCCOOMMOOTTIIOONN

3. LLOOCCOOMMOOTTIIOONN OONN LLAANNDD
Locomotion is active travel from place
to place
 It requires uussee ooff eenneerrggyy ttoo oovveerrccoommee ffoorrcceess ooff
ffrriiccttiioonn aanndd ggrraavviittyy
 TThhee rreellaattiivvee iimmppoorrttaannccee ooff ffrriiccttiioonn aanndd ggrraavviittyy
vvaarriieess ddeeppeennddiinngg oonn tthhee eennvviirroonnmmeenntt

4. Animals that crawl must overcome friction
 There are ttwwoo mmeetthhooddss ooff ccrraawwlliinngg
 SSiiddee--ttoo--ssiiddee uunndduullaattiioonn
 PPeerriissttaallssiiss ((hheeaadd--ttoo--ttaaiill wwaavveess ooff mmuussccllee
ccoonnttrraaccttiioonn))

5. HHyyddrroossttaattiicc SSkkeelleettoonnss
HHooww ddoo ssoofftt--bbooddiieedd aanniimmaallss lliikkee wwoorrmmss aanndd ootthheerr ffoorrmmss tthhaatt
llaacckk rriiggiidd sskkeelleettoonnss ooppeerraattee ooppppoossiinngg mmuusscclleess??
 They use fluid held in
internal compartments
as a hydraulic fluid to
transfer force between
opposing muscle sets.
 As muscles contract,
internal volume remains
the same, so the
opposing muscle set
must stretch.
 This stretch creates the
potential to do work

6. Figure 30.1D
1
Longitudinal
muscle
relaxed
(extended)
2
Circular
muscle
contracted
3
Bristles
Circular
muscle
relaxed
Longitudinal
muscle
contracted
Head
HHyyddrroossttaattiicc
SSkkeelleettoonn
EEaacchhEE ssaaeeggrrtmtmhheewwnntt o oiinnrr mtmthheess wwoorrmm
bbooddyy ccaann aacctt aass aann
iinnddeeppeennddeenntt hhyyddrroossttaattiicc
sskkeelleettoonn..TThhiiss ppeerrmmiittss mmuucchh
mmoorree ccoommpplleexx cchhaannggeess iinn
bbooddyy sshhaappee..
 TThhee hheeaadd iiss eexxtteennddeedd
ffoorrwwaarrdd bbyy ccoonnttrraaccttiioonn ooff
cciirrccuullaarr mmuusscclleess..
 AA wwaavvee ooff ccoonnttrraaccttiioonn ooff
lloonnggiittuuddiinnaall mmuusscclleess tthheenn
aanncchhoorrss tthhee sseeggmmeennttss nneeaarr
tthhee hheeaadd..
 AAnn eeaarrtthhwwoorrmm ccrraawwllss bbyy
ppeerriissttaallssiiss earthworm locomotion

7. Movement on land
 Gravity hhaass aa ggrreeaatt eeffffeecctt oonn llaanndd aanniimmaallss
 BBuutt ffrriiccttiioonn hhaass lliittttllee eeffffeecctt
 AAnniimmaallss mmuusstt bbee aabbllee ttoo ssuuppppoorrtt
tthheemmsseellvveess aaggaaiinnsstt tthhee ffoorrccee ooff ggrraavviittyy
 TThheeyy mmuusstt aallssoo mmaaiinnttaaiinn bbaallaannccee

8. Hopping, walking, running, and crawling are
methods of movement on land
 LLeeggss ssttaabbiilliizzee tthhee
bbooddyy aanndd pprrooppeell
tthhee aanniimmaall ffoorrwwaarrdd
 MMuusscclleess ggeenneerraattee
ppoowweerr ffoorr
mmoovveemmeenntt
 SSpprriinnggyy ssttrroonngg
bbaacckk lleeggss ssttoorree
eenneerrggyy ffoorr eeaacchh
sstteepp oorr jjuummpp
Figure 30.1B, C

11. The Stages ooff JJuummppiinngg iinn AA FFrroogg
Long hind legs are folded in the shape of Z when the
frog prepare to jump.
Hind legs becomes straight when the frog jumps.
Forelimbs stretched to outside when
the frog prepares to land.

12. Locomotion in Animals with Exoskeletons
Exoskeletons are hardened outer
surfaces to which internal
muscles are attached.
See Fig. 49.27
Increased leg length allows
greater speed and power in
locomotion (simple lever
systems)

13. Antagonistic Muscles of A Grasshopper
Human Grasshopper
Biceps
contracts
Triceps
relaxes
Forearm
flexes
Biceps
relaxes
Triceps
contracts
Forearm
extends
Extensor
muscle
relaxes
Tibia
flexes
Flexor
muscle
contracts
Extensor
muscle
contracts
Flexor
muscle
relaxes
Tibia
extends

14. The Stages of JJuummppiinngg iinn AA GGrraasssshhooppppeerr
The hind legs are folded in the shape of Z in the
position at rest (flexor muscles contract).
Extensor muscles contract. The legs of the
grasshopper jerk backwards.
The grasshopper propels forward and upward into
the air.

15. Locomotion in water:Fish
• Fish have an endoskeleton
• Most of its body weight is supported by water,
thus its easy to overcome gravity pull.
• Water is denser than air (800 times).
15

16. LOCOMOTION IN WATER: FISH
Gravity has little eeffffeecctt oonn aaqquuaattiicc aanniimmaallss
BBuutt ffrriiccttiioonn sslloowwss tthheemm ddoowwnn
Drag is minimized by the streamlined shape of the fish and
special slime fishes excrete from their skin that minimizes
frictional drag and maintains laminar (smooth) flow of water
past the fish.
When Thrust > Drag,
we have swimming!

17. AADDAAPPTTAATTIIOONNSS
 SSttrreeaammlliinneedd sshhaappee ffoorr ccuuttttiinngg tthhrroouugghh wwaatteerr
 OOvveerrllaappppiinngg ssccaalleess tthhaatt ffaaccee bbaacckkwwaarrddss..
 SSlliimmyy ccooaattiinnggss oonn ffiisshh bbooddiieess ttoo mmiinniimmiissee ffrriiccttiioonnaall
ddrraagg..
 HHaass ffiinnss..
SSCCAALLEESS

18. 18
Recognize the fins

19. AADDAAPPTTAATTIIOONNSS
• AAnnaall aanndd ddoorrssaall ffiinnss control
roll.
• Paired ppeellvviicc ((bbaacckk)) ffiinnss
ccoonnttrroollss ppiittcchh
• Paired ppeeccttoorraall ((ffrroonntt)) act
as rudders and control pitch
(up-down) and yaw (side to
side). Also acts as brakes by
causing drag.
• CCaauuddaall ((ttaaiill)) ffiinn provides
thrust & fish direction.
• SSwwiimm bbllaaddddeerr provides
neutral buoyancy.

20. AADDAAPPTTAATTIIOONNSS
TThhee BBoonnyy FFiisshh
 BBoonnyy sskkeelleettoonn ffoorr ssuuppppoorrtt ooff mmuusscclleess..
 MMyyoottoommee mmuussccllee bblloocckkss fflleexx tthhee bbooddyy,, eessppeecciiaallllyy tthhee ttaaiill..
 SSwwiimm bbllaaddddeerr pprroovviiddeess nneeuuttrraall bbuuooyyaannccyy..
 LLaatteerraall lliinnee oorrggaann ddeetteeccttss cchhaannggeess iinn pprreessssuurree ssoo iitt ccaann
iinnddiiccaattee tthhee ddeepptthh..
Spinal cord
Nostril Brain
Dorsal fin Adipose fin
Swim bladder
(characteristic of
trout)
Caudal
fin
Cut edge of
operculum Gills
Heart
Liver
Kidney Stomach
Intestine
Gonad
Anus
Urinary
bladder
Anal fin
Lateral
line
Pelvic fin
Figure 34.16

21. FFiisshh MMuusscclleess
W shaped muscle segments on both sides of backbone act antagonistically.
Alternating waves of contraction and relaxation start from head to tail on either side
of body.
Body of fish will sweep from side to side and push the water backwards and
sideways. The fish will move forward.

22. • The vertebral column is
flexible.
• The muscle in fish body is
W in shape, known as
myotome muscle
22

23. 1. When the right muscles
contract, the left muscles
relax, and the tail moves
to the right
2. When the left muscle
contract, the right
muscles relax, and the
tail moves to the left
23
3
2
1

24. Flying is the locomotion method of only a few
animal groups
 BBiirrddss,, bbaattss,, mmoosstt iinnsseeccttss,,
aanndd ssoommee eexxttiinncctt rreeppttiilleess

25. FFLLYYIINNGG IINN AA BBIIRRDD
FFeeaattuurreess
 FFeeaatthheerrss: Stiff fflliigghhtt ffeeaatthheerrss extend the surface area of the arm to produce
an aaeerrooffooiill wing.
 Stiff ttaaiill ffeeaatthheerrss control direction and velocity (air braking on landing).
 BBooddyy ffeeaatthheerrss insulate providing protection at high altitude and conserve
body heat to maintain a high metabolic rate.
 Feathers airproof, waterproof.
 Well developed cchheesstt mmuusscclleess to power the wings.
 KKeeeell bboonnee projects from thorax to attach flight muscles.
 HHoollllooww aaiirr--ffiilllleedd bboonneess provide strength but remain light.
 A hhoorrnnyy bbeeaakk is lighter than jaws and teeth.
 AAiirr ssaaccss in the abdomen permit breathed air to travel twice through the
lung tissues.
 HHaaeemmoogglloobbiinn with a high affinity for oxygen permits
flight at high altitude.
 The eemmbbrryyoo ddeevveellooppss eexxtteerrnnaallllyy in a shelled egg.
Female birds are not weighed down by pregnancy

27. Wings must develop enough lift to completely
overcome the downward pull of gravity
 Lift is generated by the aaiirrffooiill ssttrruuccttuurree ooff tthhee
wwiinngg –– aaiirr hhaass ttoo ttrraavveell aa ggrreeaatteerr ddiissttaannccee oovveerr
tthhee ttoopp tthhaann tthhee bboottttoomm-- aanndd tthhiiss ggeenneerraatteess lliifftt
Airfoil

28. Flight-caused by flapping of wings
scapula
Antagonistic muscles
Pectoralis major
Pectoralis minor
humerus coracoid
Pectoralis major Pectoralis minor

29. Pectoralis major contracts
Pectoralis minor relax
Wings pulled down
Pectoralis major relax
Pectoralis minor contracts
Wings pulled up

31. The end!