SUPPORTSYSTEMS IN

ANIMALS

RE-PURPOSED BY

CHARISSA PRETORIUS

3 TYPES OF SKELETON• ENDOSKELETON (INTERNAL

SKELETON)

• EXOSKELETON (EXTERNAL HARD SKELETON)

• HYDROSTATIC SKELETON (NO SKELETON)

ENDOSKELETON• SKELETON INSIDE THE BODY.

• FISH, AMPHIBIANS, BIRDS, MAMMALS ETC. HAVE SKELETONS MADE OF BONE.

• ANIMALS SUCH AS SHARKS, DOGFISH, RAYS, AND SKATES HAVE A SKELETON WHICH IS MADE SOLELY OF CARTILAGE.

EXOSKELETON

•SKELETON OUTSIDE THE BODY.

•FOR EXAMPLE CRABS AND PRAWNS.

• SKELETON MADE UP OF CHITIN.

• HAS JOINTS AND MUSCLE ATTACHMENT FOR MOVEMENT, BUT DOES NOT ALLOW FOR GROWTH SO ANIMALS HAVE TO SHED IT AND IT TAKES WHILE FOR THEIR NEW ONE TO HARDEN (VULNERABLE).

HYDROSTATIC SKELETON • ANIMALS WITHOUT SKELETONS.

• ANIMALS THAT DO NOT HAVE A SKELETON CAN GET QUITE LARGE AS THE WATER SUPPORTS THEM.

• FLUID PRESSURE INSIDE AN EARTHWORM IS ENOUGH TO SUPPORT IT SO IT DOES NOT NEED A SKELETON.

STRUCTURE OF THE

SKELETON

STRUCTURE OF THE SKELETON• TWO SECTIONS:

‐ AXIAL SKELETON: CRANIUM, VERTEBRAE, RIBS.

‐ APPENDICULAR SKELETON: LIMBS (ARMS AND LEGS).

• AXIAL SKELETON SUPPORTS AND PROTECTS ORGANS OF HEAD, NECK AND TRUNK.

• APPENDICULAR SKELETON- BONES OF LIMBS AND BONES THAT ANCHOR THEM TO THE AXIAL SKELETON.

AXIAL SKELETON• SKULL (CRANIUM AND

FACIAL BONES)

THE SKULL• 8 INTERLOCKING SUTURED BONES IN

CRANIUM.

• FACIAL BONES: 13 SUTURED BONES, 1 MANDIBLE (THE LOWER JAW-BONE OR MANDIBLE IS HINGED TO THE CRANIUM, SO YOU CAN CHEW).

• CRANIUM- ENCASES BRAIN, ATTACHMENTS FOR MUSCLES, SINUSES.

AXIAL SKELETON

• VERTEBRAL COLUMN

(VERTEBRAE AND DISCS)

VERTEBRAL COLUMN• 12 THORACIC VERTEBRAE ARE PART OF

THORACIC CAGE, WHICH HELPS TO PROTECT ORGANS.

• INTERMEDIATE IN SIZE.

• VERTEBRAE GET LARGER AS THEY PROGRESS DOWN THE SPINE.

• LUMBAR VERTEBRAE ARE THE LARGEST.

• DUE TO AMOUNT OF MOVEMENT OCCURRING HERE- OFTEN SITE OF BACK PAIN.

• SACRAL VERTEBRAE ARE FUSED: JOINS TWO HALVES OF PELVIS TOGETHER.

• COCCYX ATTACHED TO BOTTOM OF SACRUM.

VERTEBRAL COLUMN

•7 CERVICAL VERTEBRAE

•12 THORACIC VERTEBRAE

•5 LUMBAR VERTEBRAE

•1 SACRUM (5 FUSED VERTEBRAE)

•1 COCCYX (4 FUSED VERTEBRAE)

VERTEBRAL COLUMN• THE FIRST VERTEBRA IS CALLED THE

ATLAS- SUPPORTS THE SKULL.

• THE SECOND VERTEBRA IS CALLED THE

AXIS AND FORMS A PIVOT JOINT WITH THE

ATLAS.

VERTEBRAE • EACH VERTEBRAE HAS A HOLE IN TO ALLOW

SPINAL CORD TO PASS DOWN THROUGH IT.

• PROTECTS SPINAL CORD.

• IN BETWEEN EACH VERTEBRAE IS A DISC: PREVENTS FRICTION AND ACTS AS SHOCK ABSORBER.

AXIAL SKELETON• THORACIC CAGE

(RIBS AND STERNUM)

THE THORACIC CAGE

• CONSISTS OF RIBS, THORACIC VERTEBRAE,

STERNUM AND COSTAL CARTILAGES.

• YOU HAVE 12 PAIRS OF RIBS.

• ALL ARE JOINED TO THE THORACIC

VERTEBRAE.

True ribs are directly

attached to the sternum

(first seven pairs)

Two pairs of floating ribs

Three false ribs are joined to the 7th rib

APPENDICULAR SKELETON• CLAVICLES

• SCAPULAE

• HUMERUS

• RADIUS

• ULNA

• CARPALS

• METACARPALS

• PHALANGES

• ILIUM

• PUBIS

• ISCHIUM

• FEMUR

• PATELLA

• TIBIA

• FIBULA

• TARSALS AND METATARSALS

All the bones not in the axial skeleton

THE SHOULDER GIRDLE• EACH CLAVICLE

ARTICULATES, AT THE TOP OF THE SHOULDER, WITH THE SCAPULA (ACROMIAL-CLAVICULAR JOINT) AND

• AT THE OPPOSITE END, AT THE FRONT WITH THE STERNUM (STERNO-CLAVICULAR JOINT)

CLAVICLES AND SCAPULAE

• HELP BRACE

SHOULDERS.

• ATTACHMENT

SITES FOR

MUSCLES.

BONES OF UPPER LIMB• HUMERUS (UPPER ARM).

• RADIUS AND ULNA (FOREARM).

• CARPALS, METACARPALS, PHALANGES (WRIST, HAND AND FINGERS).

BONES OF LOWER LIMB• FEMUR (THIGH).

• PATELLA (KNEE CAP).

• TIBIA, FIBULA (LOWER LEG).

• TARSALS, METATARSALS, PHALANGES (ANKLE, FOOT AND TOES).

Cranium

Clavicle

Rib

SternumHumerus

RadiusUlna

CarpalsMetacarpals Phalange

s

Ilium

Ischium

Pubis

FemurPatellaFibula

TibiaTarsals

Metatarsals

Phalanges

Scapula

Cervical Spine

Thoracic Spine

Lumbar SpineSarcral Spine

Coccyx

206 BONES IN THE SKELETON• 22 BONES IN SKULL

• 6 IN MIDDLE EARS

• 1 HYOID BONE

• 33 IN VERTEBRAL COLUMN

• 25 IN THORACIC CAGE

• 4 IN PECTORAL GIRDLE

• 60 IN UPPER LIMBS

• 60 IN LOWER LIMBS

• 2 IN PELVIC GIRDLE

STRUCTURE OF THE

BONE

STRUCTURE OF BONE COMPACT BONE (CORTICAL)

• HARD AND DENSE BONE.

• MAKES UP MAIN SHAFT OF BONES AND OUTER LAYER.

• CELLS IN THIS BONE ARE LOCATED IN RINGS OF BONE TISSUE AROUND A CENTRAL HAVERSIAN CANAL, CONTAINING NERVES AND BLOOD VESSELS.

• THE BONE CELLS (OSTEOCYTES) LIVE IN SPACES (LACUNAE) BETWEEN THE RINGS.

• EACH RINGED UNIT MAKES UP A HAVERSIAN SYSTEM.

• ARRANGED IN CONCENTRIC CIRCLES CALLED LAMELLAE.

• CANALICULI CONNECT OSTEOCYTES TO CENTRAL CANAL AND TO EACH OTHER.

STRUCTURE OF BONE SPONGY BONE (CANCELLOUS)

• LESS DENSE- MORE SPACES (CRUNCHIE BAR).

• MESH OF SMALL BONY PLATES FILLED WITH RED MARROW.

• FOUND IN EPIPHYSES OF LONG BONES AND CENTRE OF OTHER BONES.

BONE MARROW

• RED MARROW:

• FOUND IN THE ENDS OF LONG BONES AND CENTRE OF OTHER BONES

• MANUFACTURES BLOOD CELLS

• YELLOW MARROW:

• IN CENTRAL CAVITIES OF LONG BONES

• COMPOSED MAINLY OF FAT

STRUCTURE OF BONE

PERIOSTEUM

• MEMBRANE COVERING BONE (NOT JOINTS).

• INNER LAYER OF MEMBRANE CONTAINS. OSTEOBLASTS- HELPS TO REPAIR INJURIES.

• BLOOD VESSELS HELP TO NOURISH.

ENDOSTEUM

• MEMBRANE LINES BONES MARROW CAVITY.

STRUCTURE OF LONG BONE• BONE ENCLOSED IN PERIOSTEUM A CONTINUOUS SHEATH, WITH

TENDONS AND LIGAMENTS, BLOOD VESSELS IN PERIOSTEUM.

• EPIPHYSIS- PROXIMAL AND DISTAL ENDS OF BONE.

• INNER- SPONGY BONE CONTAINS RED MARROW.

• OUTER- COMPACT BONE, ARTICULAR CARTILAGE.

• DIAPHYSIS- MIDDLE

• OUTER- COMPACT BONE.

• INNER- MEDULLARY CAVITY- CONTAINS YELLOW MARROW (FAT) AND LINED WITH ENDOSTEUM (SQUAMOUS EPITHELIUM).

• NUTRIENT FORAMEN- ALLOWS FOR PASSAGE OF BLOOD VESSELS INTO MEDULLARY CAVITY.

• EPIPHYEASEAL LINE/ PLATE- WHERE GROWTH OCCURS WITHIN THE BONE.

TYPES OF BONE

FUNCTION OF THE

SKELETON

• MOVEMENT- THE SKELETON IS JOINTED TO ALLOW US TO MOVE WHEN THE MUSCLES ATTACHED TO THEM CONTRACT.

• SUPPORT- WITHOUT THE SKELETON, THE BODY WOULD BE FLABBY AND SHAPELESS.

• PROTECTION- THE HARD NATURE OF BONE MEANS THAT THE SKELETON CAN PROTECT THE MORE DELICATE PARTS OF THE BODY.

• STORAGE- MINERALS ARE STORED WITHIN THE BONES WHICH HELPS BONE GROWTH

• PRODUCTION- RED AND WHITE BLOOD CELLS ARE MADE IN RED BONE MARROW WHICH IS FOUND AT THE ENDS OF THE FEMUR AND HUMERUS AND IN THE RIBS, STERNUM, PELVIS AND VERTEBRAE.

ONE MORE IMPORTANT FUNCTION• BONES ARE LIVING TISSUE THAT GROWS AND HARDENS.

• BONE IS CARRIED OUT FROM WITHIN THE BONE AND GROWTH INVOLVES 3 FACTORS;

• OSTEOBLASTS- THESE ARE BONE FORMING CELLS THAT CREATE NEW BONE TISSUE.

• OSTEOCLASTS- THESE ARE SPECIALISED CELLS THAT REMODEL BONE BY DESTROYING BONE CELLS AND REABSORBING CALCIUM.

• EPIPHYSEAL PLATE- THE GROWTH PLATE IS THE ONLY REGION OF A LONG BONE WHICH CAN GENERATE NEW CELLS.

JOINTS

FIBROUS JOINTS• IMMOVEABLE

• CONNECT BONES WITHOUT ALLOWING ANY MOVEMENT.

• THE BONES OF YOUR SKULL AND PELVIS ARE HELD TOGETHER BY FIBROUS JOINTS.

• FIBROUS JOINTS SUPPLY PROTECTS – E.G. FOR THE BRAIN.

CARTILAGINOUS JOINTS• SEMI-MOVEABLE, THUS ALLOWS ONLY

LIMITED MOVEMENT.

• JOINTS IN WHICH THE BONES ARE ATTACHED TO EACH OTHER BY CARTILAGE.

• THESE JOINTS ALLOW FOR ONLY A LITTLE MOVEMENT, SUCH AS IN THE SPINE OR RIBS.

SYNOVIAL JOINT• FREELY MOVEABLE, AS MUCH AS THE SHAPE OF THE

ARTICULATING SURFACE WILL ALLOW.

• CAVITIES BETWEEN BONES IN JOINTS ARE FILLED WITH

SYNOVIAL FLUID (FROM A SYNOVIAL MEMBRANE) HELPS

LUBRICATE AND PROTECT THE BONES.

• JOINT ENCLOSED BY FIBROUS CAPSULE (LIGAMENTS).

• SURFACES LINED WITH CARTILAGE TO ABSORB SHOCKS AND

REDUCE FRICTION.

TYPES OF SYNOVIAL JOINTS

BALL AND SOCKET• Hip• Shoulder

TYPES OF SYNOVIAL JOINTS

HINGE JOINT

• Elbow• Knee

TYPES OF SYNOVIAL JOINTS

PIVOT JOINT

• Wrist

TYPES OF SYNOVIAL JOINTS

SADDLE JOINT

• Thumb

TYPES OF SYNOVIAL JOINTS

GLIDING JOINT

• Bones in hand

TYPES OF SYNOVIAL JOINTS

CONDYLOID JOINT

• Wrist

SKELETAL MUSCLES

SKELETAL MUSCLES

• THESE MUSCLES ARE UNDER CONSCIOUS CONTROL.

• OFTEN ATTACHED TO BONE AND ENABLE MOVEMENTS E.G. BICEPS, TONGUE ETC.

MUSCLES CONTRACTION• SKELETAL MUSCLES CAUSE THE

SKELETON TO MOVE AT JOINTS.

• THEY ARE ATTACHED TO THE SKELETON BY TENDONS, WHICH TRANSMIT THE MUSCLE FORCE TO THE BONE AND CAN ALSO CHANGE THE DIRECTION OF THE FORCE.

• TENDONS ARE MADE OF COLLAGEN FIBRES AND ARE VERY STRONG AND STIFF (I.E. NOT ELASTIC).

• THE SKELETON PROVIDES LEVERAGE, MAGNIFYING EITHER THE MOVEMENT OR THE FORCE.

• MUSCLES ARE EITHER RELAXED OR CONTRACTED.

• IN THE RELAXED STATE MUSCLE CAN BE STRETCHED.

• IN THE CONTRACTED STATE MUSCLE EXERTS A PULLING FORCE, CAUSING IT TO SHORTEN OR GENERATE FORCE.

• SINCE MUSCLES CAN ONLY PULL (NOT PUSH), THEY WORK IN PAIRS CALLED ANTAGONISTIC MUSCLES.

• THE MUSCLE THAT BENDS (FLEXES) THE JOINT IS CALLED THE FLEXOR MUSCLE, AND THE MUSCLE THAT STRAIGHTENS (EXTENDS) THE JOINT IS CALLED THE EXTENSOR MUSCLE.

ANTAGONISTIC MUSCLES

SKELETAL MUSCLES

STRUCTURE

A muscle is an organ composed of different tissues including muscle tissue, connective tissue (e.g. tendon) etc

Muscle tissue is composed of muscle cells called muscle fibres

Each muscle fibre (cell) is packed with organelles called myofibrilsMyofibrils are composed mainly of two muscle filaments called actin and myosin

Myofibrils can be divided into functional units, each called a sarcomere

MUSCLE CONTRACTION ( VIDEO )(CLICK ON VIDEO TO START)

DISEASES THAT AFFECT

THE SKELETON

OSTEOPOROSIS• AFTER THE AGE OF 35, BONE LOSS INCREASES

VERY GRADUALLY AS PART OF THE NATURAL AGEING PROCESS. THIS BONE LOSS BECOMES MORE RAPID IN WOMEN FOR SEVERAL YEARS FOLLOWING THE MENOPAUSE AND CAN LEAD TO OSTEOPOROSIS AND AN INCREASED RISK OF BROKEN BONES, ESPECIALLY IN LATER LIFE.

• HAVING OSTEOPOROSIS DOES NOT AUTOMATICALLY MEAN THAT YOUR BONES WILL BREAK, IT JUST MEANS THAT YOU HAVE A ‘GREATER RISK OF FRACTURE’.

SYMPTOMS

• SYMPTOMS OF ARTHRITIS CAN INCLUDE PAIN, SWELLING AND STIFFNESS IN JOINTS OR THE INABILITY TO MOVE A JOINT NORMALLY.

• IN SOME TYPES OF ARTHRITIS, SUCH AS RHEUMATOID ARTHRITIS, JOINTS CAN BECOME RED, WARM, SWOLLEN AND PAINFUL.

TYPES OF ARTHRITIS

• OSTEOARTHRITIS - COMMON 'WEAR AND TEAR' ARTHRITIS.

• RHEUMATOID - AN INFLAMMATORY CONDITION CAUSED BY THE IMMUNE SYSTEM.

• JUVENILE ARTHRITIS - THREE COMMON TYPES OF ARTHRITIS THAT CAN AFFECT CHILDREN.

OSTEOARTHRITIS• OSTEOARTHRITIS, A DEGENERATIVE JOINT

DISEASE IN WHICH THE CARTILAGE THAT

COVERS THE ENDS OF BONES IN THE

JOINT DETERIORATES, CAUSING PAIN AND

LOSS OF MOVEMENT AS BONE BEGINS TO

RUB AGAINST BONE. IT IS THE MOST

PREVALENT FORM OF ARTHRITIS.

RHEUMATOID ARTHRITIS• RHEUMATOID ARTHRITIS, AN

AUTOIMMUNE DISEASE IN WHICH THE JOINT LINING BECOMES INFLAMED AS PART OF THE BODY’S IMMUNE SYSTEM ACTIVITY. RHEUMATOID ARTHRITIS IS ONE OF THE MOST SERIOUS AND DISABLING TYPES, AFFECTING MOSTLY WOMEN.

RE-PURPOSED FROM...HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/TUTORIAL-ON-THE-SKELETON-SY

STEM-6307947/ ,RETRIEVED APRIL 2, 2014

HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/JOINTS-6374412/ , RETRIEVED APRIL 3, 2014

HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/SKELETAL-SYSTEM-6219726/ , RETRIEVED APRIL 3, 2014

HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/THE-SKELETON-6355594/ , RETRIEVED APRIL 3, 2014

HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/MUSCLES-AND-MUSCLE-ACTION-6093013/  , RETRIEVED APRIL 3, 2014

HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/MUSCLES-6203240/ , RETRIEVED APRIL 2, 2014

HTTP://WWW.TES.CO.UK/TEACHING-RESOURCE/DEGENERATIVE-DISEASES-6129145/ , RETRIEVED APRIL 3, 2014