bology form 5

8/7/2019 Bology Form 5

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2.1 Support System and Locomotion

in Humans and AnimalsSupport system and locomotionSupport system and locomotionLocomotionLocomotion refers to the ability of whole organism to move from one place to another.refers to the ability of whole organism to move from one place to another.

MovementMovement refers to a change in a position of any part of an organisms body it does notrefers to a change in a position of any part of an organisms body it does notnecessarily involve locomotionnecessarily involve locomotion..

SupportSupport is provided by a framework calledis provided by a framework called skeleton.skeleton.

There are three different types of skeletons in animals:There are three different types of skeletons in animals:

I.I. Exoskeleton(on the outside of theExoskeleton(on the outside of the body;externalbody;external))

a)a) Support the important internal organs and protect the internal structures from damage.Support the important internal organs and protect the internal structures from damage.

b)b) It enable the organisms to move from place to place.It enable the organisms to move from place to place.

c)c) The cuticle is covered with wax tom prevent water loss.The cuticle is covered with wax tom prevent water loss.

II.II.EndoskeletonEndoskeleton(internal)(internal)

a)a) Found in all vertebrates.Found in all vertebrates.b)b) Maintaining the body shapeMaintaining the body shape

c)c) Supporting the soft body tissuesSupporting the soft body tissues

d)d) Protecting the internal organs from injury Protecting the internal organs from injury

III.III.HydrostaticHydrostatic skeleton(made of f luid)skeleton(made of fluid)

a)Consists of internal fluids within the confined spaces of body.a)Consists of internal fluids within the confined spaces of body.



Support and

locomotion with an

endoskeleton

1.1. TheThe human skeletonhuman skeletonconsists mainly of consists mainly of bonesbones but a few partsbut a few partssuch as the nose, ears,such as the nose, ears,and the soft discsand the soft discs

between the vertebratebetween the vertebrateare made of are made of cartilage.cartilage.2.2. The skeleton has twoThe skeleton has two

main parts themain parts the axialaxialskeletonskeleton and theand theappendicularappendicular skeletonskeleton..

3.3. TheThe axial skeletonaxial skeletona)Consists of a)Consists of the skull,the skull, vertebral, vertebral, column,ribscolumn,ribs,,and sternum.and sternum.



Support and locomotion with an

endoskeleton1.The skull consists 22 bones, rests

on top of the vertebral column.

2. It includes:

a) The cranial bones whichenclose and protect the brain,and

b) The facial bones which protectand provide support for theentrances to the digestive andrespiratory system.

3. The bones which make up theskull are held securely together by immovable jointscalled sutures.



yy Thoracic cageThoracic cageyy TheThe thoraxthorax consists of a skeletonconsists of a skeleton

portion called theportion called the thoraricthoraric cage.cage.

I.I. Thoracic encloses and protectsThoracic encloses and protectsthe organs in the thoracic cavity the organs in the thoracic cavity and upper abdominal cavity,and upper abdominal cavity,

yy Twelve pairs of Twelve pairs of ribsribs make up themake up thesides of the thoracic cavity. They sides of the thoracic cavity. They articulate with twelve vertebrate of articulate with twelve vertebrate of the thoracic region.the thoracic region.

yy The sternum or breastbone is flat,The sternum or breastbone is flat,narrow bone located in the centrenarrow bone located in the centreof theof the enteriorenterior thoracic wall.thoracic wall.

The vertebral columna. Encloses and protects the spinalspinal

cordcordb.b. Support the headSupport the headc.c. Serve as a point of attachmentServe as a point of attachment

for thefor the ribs,pelvicribs,pelvic girdle and thegirdle and themuscle of the backmuscle of the back

Has 33 vertebrate consists of Has 33 vertebrate consists of a.a. 7 cervical vertebrate7 cervical vertebrateb.b. 1212 thoraricthoraric vertebrate vertebratec.c. 5 lumber vertebrate5 lumber vertebrated.d. 5 sacral lumbar(sacrum)5 sacral lumbar(sacrum)

e.e. 4 caudal vertebrate(coccyx)4 caudal vertebrate(coccyx)



The vertebratevertebrate

a) atypical vertebrate has a centrumcentrum,, an opening

called vertebral foramen and processes.processes.

b) the spinal cord goes the vertebral foremen

yy Cervical vertebraCervical vertebrayy

Have transverse foramenHave transverse foramenthrough which blood vesselsthrough which blood vesselsand nerve pass.and nerve pass.

yy Thoracic vertebraThoracic vertebrayy

HaveHave spinousspinous processesprocessesthat are long and directthat are long and directdownwards.downwards. SpinousSpinous andandtransverse processes servetransverse processes serveas points of attachment of as points of attachment of muscles and ligaments.muscles and ligaments.



Sacrum and coccyxSacrum and coccyx

TheThe sacrumsacrum is a triangulartriangularbone formed throughbone formed throughthe fusion of five bones.the fusion of five bones.

TheThe coccyxcoccyx is alsois alsotriangular in shape andtriangular in shape andformed through theformed through thefusion of 4 bones.fusion of 4 bones.

yy TheThe appendicularappendicularskeletonskeleton

yy

Consists of the pectoralConsists of the pectoralgardle,uppergardle,upperlimbs,pelviclimbs,pelvic girdle, andgirdle, andthe lower limbsthe lower limbs

yy TheThe pectorapectora girdlegirdle

yy Consists of 2 bones: theConsists of 2 bones: theclavicle and the scapula.clavicle and the scapula.



yy TheThe clavicleclavicle ororcollarbone,iscollarbone,is long,sladderlong,sladder

SS--shape bone that isshape bone that ispositionedpositioned horizontolly horizontolly above the first rib.above the first rib.

yy TheThe scapula,scapula,oror shouldershoulder

blade, is ablade, is a large,flatlarge,flat,,triangular bone situatedtriangular bone situatedin the posterior of thein the posterior of thethorax.thorax.



The lower limblower limby The femurfemur isis longest,heaviestlongest,heaviest andand

strongest bone the body.strongest bone the body.

yy The head of the femur forms aThe head of the femur forms a ballball--

and socket jointand socket joint with the hip bone. with the hip bone.yy The other end of the femur forms aThe other end of the femur forms a

hinge jointhinge joint with the tibia. with the tibia.

yy TheThe patella,patella, oror kneecap,iskneecap,is a smalla smalltriangular protects thetriangular protects the knee joint,knee joint, aahinge joint.hinge joint.

yy TheThe tibiatibia bears the weight of thebears the weight of thebody.body.

yy TheThe fibula,fibula, which is parallel to the which is parallel to the

tibia,istibia,is smaller than tibia.smaller than tibia.yy TheThe tartustartus or theor the ankleankle of the footof the foot

contains 7 bones calledcontains 7 bones called tartalstartals..

yy 5 bones called the5 bones called the metatarsalsmetatarsals fromfromthe skeleton of the metatarsus.the skeleton of the metatarsus.



The structure of a jointy Flexible connentive tissue from joints

holding bones together to allowmovements.

yy A joint A joint is the place where 2 or morebones meet.

a) At a joint, the bones are held

together by though sheets of elasticfibres called ligaments.

b) They allow bones to move against 1another and prevent the dislocationof the joint during movement.

c) A synovial joint is a joint which has acavity filled with fluid.

d) Synovial joints are freely movable.

e) A typical synovial joint has 4

maintains features.



The synovial membrane secretesThe synovial membrane secretes synovial fluidsynovial fluidintointo the synovial cavity the synovial cavity..

The synovial fluid acts as a lubricant whichThe synovial fluid acts as a lubricant whichreduces the friction between the ends of thereduces the friction between the ends of the

bones.bones.The end surfaces of the bones are covered withThe end surfaces of the bones are covered withcartilage.cartilage.

TheThe cartilagecartilage cushion the joints, absorbs shockcushion the joints, absorbs shockand reduces the friction between the ends of and reduces the friction between the ends of

bones.bones.The cartilage also protects the bones fromThe cartilage also protects the bones from wearing away. wearing away.

The inner surface of the capsule is lined with aThe inner surface of the capsule is lined with athin layer of thin layer of synovial membrane.synovial membrane.

TheThe joint capsule is joint capsule is an enclose reinforced by andan enclose reinforced by andstrengthened with ligaments.strengthened with ligaments.



Hinge joint Ball- and- socket joint

yy A hinge joint allows the

A hinge joint allows themovement of bonesmovement of bones in onein one

plane. plane.

yy Hinge joints are found in theHinge joints are found in theelbows, phalanges of the fingerelbows, phalanges of the finger

and toes, and in the knees.and toes, and in the knees.yy A knee joints allows the lower leg A knee joints allows the lower leg

to swing back and forth, like ato swing back and forth, like ahinge on a door.hinge on a door.

yy A ball A ball andand-- socket joint allowssocket joint allowsrotational movement of bonesrotational movement of bones ininall directions.all directions.

yy It allows the swinging of armsIt allows the swinging of armsand legs in a circular motion.and legs in a circular motion.

yy Examples of a ballExamples of a ball--andand socketsocket

are theare the shoulder jointshoulder joint betweenbetweenthethe humerushumerus and the pectoraland the pectoralgirdle, and thegirdle, and the hip jointhip joint betweenbetweenthe femur and the pelvic girdle.the femur and the pelvic girdle.



What are tendons and skeleton

muscles?Tendons

Skeletonmusclesy Skeletal muscle are responsible for

the voluntary movements of thebody.

y They are attached 2 bones across joints through the tendons.tendons.

y The bones of the skeleton to which

the muscle are attached operate aslevers,levers,yy Skeletal muscle produce movementsSkeletal muscle produce movements

by exerting the force to pull on theby exerting the force to pull on thetendons which are attached totendons which are attached tobones.bones.

yy A s a muscle contracts, it becomes A s a muscle contracts, it becomesshorter as it pulls on the attachedshorter as it pulls on the attachedbone.bone.

yy Since a muscle cannot push, but only Since a muscle cannot push, but only pull, it has to be extended back to itspull, it has to be extended back to itsoriginal length by the opposingoriginal length by the opposingaction of another muscle.action of another muscle.

1. Tendons are tough, strong,and elastic strands of denseconnective tissues.

2. Tendons join skeletalskeletalmusclesmuscles to the bones.



How movement is brought about in

a limb1. tr i htening the f orearm 2.Bending the f orearm

y Whe the tric s c tr cts athe bic s r l x s, the f rearis strai hte e .

y W hen the biceps contracts,

the tendons transmit thepulling force by thecontraction to the forearm.

y A t the same time, the tricepsrela es.

y A s the result ,the elbow jointbends, the forearm movesupward.



The structure of a muscle

y 1. Skeleton muscle such as thebiceps consists of bundles of muscle fibres and large supply of nerves and blood vessels.

y 2. A muscle A muscle fibre fibre is a longcylindrical cell that containsnumerous nuclei.

y 3. A large skeleton musclecontains thousands of such cells.

y 4

y 4. A muscle fibre is made of bundles of smaller units calledmyofibrils.myofibrils.

y 5. Each myofibril is made up of 2

types of protein filaments: protein filaments:actinactin and myosin.and myosin.

yy 6. The interaction of both these6. The interaction of both theseproteins causesproteins causes musclemusclecontractions.contractions.



CONSEQUENCES OF MUSCULO

SKELETAL SYSTEM ON SUPPORT AND

LOCOMATIONy The musculoskeletal consists of bones, joints,bones, joints,

muscle, ligaments and tendons.muscle, ligaments and tendons.

yy The musculoskeletal system can be impaired either by:The musculoskeletal system can be impaired either by:

a)a) Diseases orDiseases or

b)b) Muscle that do not contract in a coordinated way Muscle that do not contract in a coordinated way

A ffects A ffects

1.1. Muscle crampsMuscle cramps2.2. Muscular dystrophy Muscular dystrophy

3.3. OsteoporosisOsteoporosis

4.4. A rthritis A rthritis



Muscle cramps

1. A muscle cramps is suddencontraction of one or more

muscle.2. A muscle cramps is an

involuntary, forcibly whencontracted muscle that isnot able to relax.

3. W hen cramps begins, thespinal cord stimulates themuscle to keep contracting.

4. Usually affected are the back

of the lower leg or the calf,the back of thigh(hamstrings) or the front of the thigh (the quadriceps).

Muscular dystrophy

y M uscular dystrophy iscaused by the progressive

degeneration and weakeningof the skeletal muscle thatcontrol movement.

y The body muscle gradually become weak as they arereplaced by fibrous tissue.

y this diseases is caused by mutated gene in the X chromosome and mainly

affects boys.



Osteoporosisy Common bone disorder which causes the bones to

became thinner, more brittle and more porous.y The loss of bone mass normally begins the elderly

women after the age of 30 years and accelerates greatly after the age of 45 years. It particularly affects women

after menopause, when changes in hormone levels.y During the course of individuals life, the body needs

phosphate and calcium to build bones.

y Osteoporosis can be prevent by taking adequate

amounts of calcium, phosphorus and vitamin D.y R egular exercise can also reduce the likelihood of

bone fractures and help reduce bone minerals loss.



y Most people are no aware that they have osteoporosisuntil a bone is fractured because there are nosymptoms or early signs of osteoporosis.



Arthritisy A group of skeleton disorders that involve

inflammation of the joint.y The joints becomes swollen, stiff and painful.

y One form of arthritis is osteoarthritis.

y Osteoarthritis is part of the ageing process caused by

the wear and tear of the cartilage between the bonesinside certain joints.y The ageing process may also result in decreased

production of the synovial fluid in the joints.

y The patient usually suffers from a painful and stiff knee which restricts daily activities such as walkingand climbing.

y If treatment fails to relieve that pain, a surgeon canreplace the damage joints with artificial ones made of

plastic or metals.



The End

that all from us.Thank you

bology form 5

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