The document describes the three main types of skeletons - endoskeleton, exoskeleton, and hydrostatic skeleton. It then goes into detail about the human skeletal system, including the structure and types of bones, joints, and muscles. Key points include that humans have an endoskeleton made of bone, the skeletal system is divided into the axial skeleton and appendicular skeleton, and there are three main types of joints - fibrous, cartilaginous, and synovial joints.

2. 3 TYPES OF SKELETON
• ENDOSKELETON (INTERNAL SKELETON)
• EXOSKELETON (EXTERNAL HARD
SKELETON)
• HYDROSTATIC SKELETON (NO SKELETON)

3. ENDOSKELETON
• SKELETON INSIDE THE BODY.

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

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

6. EXOSKELETON
•SKELETON OUTSIDE THE BODY.
•FOR EXAMPLE CRABS AND PRAWNS.

7. • 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).

8. HYDROSTATIC SKELETON
• ANIMALS WITHOUT SKELETONS.

9. • 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.

11. STRUCTURE OF THE
SKELETON
• TWO SECTIONS:
‐ AXIAL SKELETON: CRANIUM, VERTEBRAE,
RIBS.
‐ APPENDICULAR SKELETON: LIMBS (ARMS
AND LEGS).

12. • 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.

14. AXIAL SKELETON
• SKULL (CRANIUM AND
FACIAL BONES)

15. 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.

17. AXIAL SKELETON
• VERTEBRAL COLUMN
(VERTEBRAE AND DISCS)

18. 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.

19. • 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.

20. VERTEBRAL COLUMN
•7 CERVICAL VERTEBRAE
•12 THORACIC VERTEBRAE
•5 LUMBAR VERTEBRAE
•1 SACRUM (5 FUSED VERTEBRAE)
•1 COCCYX (4 FUSED VERTEBRAE)

22. 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.

23. 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.

24. AXIAL SKELETON
• THORACIC CAGE
(RIBS AND STERNUM)

25. 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.

26. 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

27. 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

28. 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)

29. CLAVICLES AND SCAPULAE
• HELP BRACE
SHOULDERS.
• ATTACHMENT
SITES FOR
MUSCLES.

30. BONES OF UPPER LIMB
• HUMERUS (UPPER ARM).
• RADIUS AND ULNA
(FOREARM).
• CARPALS, METACARPALS,
PHALANGES (WRIST, HAND
AND FINGERS).

31. BONES OF LOWER LIMB
• FEMUR (THIGH).
• PATELLA (KNEE CAP).
• TIBIA, FIBULA (LOWER
LEG).
• TARSALS, METATARSALS,
PHALANGES (ANKLE,
FOOT AND TOES).

32. Cranium
Clavicle
Rib
Sternum
Humerus
Radius
Ulna
Carpals
Metacarpals
Phalanges
Ilium
Ischium
Pubis
Femur
PatellaFibula
Tibia
Tarsals
Metatarsals
Phalanges
Scapula
Cervical Spine
Thoracic Spine
Lumbar Spine
Sarcral Spine
Coccyx

33. 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

35. STRUCTURE OF BONECOMPACT 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.

36. 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

37. 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.

38. 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.

41. TYPES OF BONE

43. • 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.

44. 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.

46. 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.

47. 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.

48. 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.

49. TYPES OF SYNOVIAL
JOINTS
BALL AND SOCKET
• Hip
• Shoulder

50. TYPES OF SYNOVIAL
JOINTS
HINGE JOINT
• Elbow
• Knee

51. TYPES OF SYNOVIAL
JOINTS
PIVOT JOINT
• Wrist

52. TYPES OF SYNOVIAL
JOINTS
SADDLE JOINT
• Thumb

53. TYPES OF SYNOVIAL
JOINTS
GLIDING JOINT
• Bones in hand

54. TYPES OF SYNOVIAL
JOINTS
CONDYLOID JOINT
• Wrist

56. SKELETAL MUSCLES
• THESE MUSCLES ARE UNDER CONSCIOUS
CONTROL.
• OFTEN ATTACHED TO BONE AND ENABLE
MOVEMENTS E.G. BICEPS, TONGUE ETC.

57. 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.

58. • 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.

59. • 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.

60. • 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.

61. ANTAGONISTIC MUSCLES

63. 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 myofibrils
Myofibrils are composed mainly of two
muscle filaments called actin and
myosin
Myofibrils can be divided into
functional units, each called a
sarcomere

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

67. 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.

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

69. 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.

70. 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.

71. 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.

73. 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.

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