The Skeleton
Upcoming SlideShare
Loading in...5

Like this? Share it with your network

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads


Total Views
On Slideshare
From Embeds
Number of Embeds



Embeds 19 19

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

    No notes for slide


  • 1. THE SKELETAL SYSTEMDesigned by: A. Sokolova, M.Martova, O. Sykorsky, D.Levachov
  • 2. The skeletal systemStructure and function ofboneOrganization of theskeletonJoints
  • 3. Functions of bone (skeleton)Support and protectionBlood cell formationMineral storage (calcium especially)Site for muscle attachment→body movement
  • 4. Bones classified by shape: long, short, flat, irregular, roundBone enclosed in periosteum, which is continuous with tendons and ligaments blood vessels in periosteumEpiphysis- ends spongy bone contains red marrow compact bone, articular cartilageDiaphysis- middle compact bone medullary cavity- contains yellow marrow (fat) lined with endosteum (squamous epithelium)
  • 5. Compact bone osteocytes within lacunae arranged in concentric circles called lamellaeThis surround a central canal; complex is called Haversian systemCanaliculi connect osteocytes to central canal and to each other
  • 6. Prenatal development skeleton is mostly cartilaginousCartilage cells and then osteoblasts start to deposit mineralsCartilaginous disk (epiphyseal disk) remains in epiphysisCells eventually stop dividing
  • 7. Adults continually break down and build up boneOsteoclasts remove damaged cells and release calcium into bloodOsteoblasts remove calcium from blood and build new matrix. They become trapped→ osteoclasts
  • 8. Types of bone breaksSimple- skin is not piercedCompound- skin is piercedComplete- bone is broken in halfPartial- broken lengthwise but not into two partsGreenstick- incomplete break on outer arcComminuted- broken into several piecesSpiral- twisted
  • 9. Fracture repairHematoma- blood clot in space between edges of breakFibrocartilage callus- begins tissue repairBony callus- osteoblasts produce trabeculae (structural support) of spongy bone and replace fibrocartilageRemodeling- osteoblasts build new compact bone, osteoclasts build new medullary cavity
  • 10. Axial skeleton skull (cranium and facial bones) hyoid bone (anchors tongue and muscles associated with swallowing) vertebral column (vertebrae and disks) thoracic cage (ribs and sternum)Appendicular skeleton pectoral girdle (clavicles and scapulae) upper limbs (arms) pelvic girdle (coxal bones, sacrum, coccyx) lower limbs (legs)
  • 11. posterior viewp. 135
  • 12. Bones named and numbered in Table 7.1 on page 137Terms listed in table 7.2 (same page)Axial skeleton supports and protects organs of head, neck and trunkAppendicular skeleton- bones of limbs and bones that anchor them to the axial skeletonArticulation- where joints are formed
  • 13. 22 bones in skull6 in middle ears1 hyoid bone26 in vertebral column25 in thoracic cage4 in pectoral girdle60 in upper limbs60 in lower limbs2 in pelvic girdle206 bones in all
  • 14. The skull8 sutured bones in craniumFacial bones: 13 sutured bones, 1 mandibleCranium encases brain attachments for muscles sinuses
  • 15. Allows forgrowth
  • 16. Vertebral column7 cervial vertebrae12 thoracic5 lumbar1 sacrum (5 fused1 coccyx (4 fused)Vertebrae vary in size and morphology
  • 17. Thoracic cage ribs thoracic vertebrae sternum costal cartilagesTrue ribs are directly attached to the sternum(first seven pairs)Three false ribs are joined to the 7th ribTwo pairs of floating ribs
  • 18. Clavicles and scapulaeHelp brace shouldersAttachment sites for muscles
  • 19. Bones of upper limbHumerus (upper arm)Radius; ulnaCarpals, metacarpals, phalangesBones of lower limbFemurPatellaTibia, fibulaTarsals, metatarslas, phalanges
  • 20. JointsImmovable (synarthoses) bones sutured together by connective tissue: skullSlightly movable (amphiarthoses) connected by fibrocartilage or hyaline cartilage: vertebrae, rib/sternum joint, pubic symphysisFreely movable (diarthroses)- separated ligaments- hold bones together tendons- muscle to bone lined by synovial membrane
  • 21. Types of freely movable jointsSaddle: carpal and metacarpal bones of thumbBall and socket: shoulder and hip jointsPivot- rotation only: proximal end of radius and ulnaHinge- up and own movement in one plane: knee and elbowGliding- sliding and twisting: wrist and ankleCondyloid- movement in different planes but not rotations: btw metacarpals and phalanges
  • 22. Types of movement and examples (with muscles) flexion- move lower leg toward upper extension- straightening the leg abduction- moving leg away from body adduction- movong leg toward the body rotation- around its axis supination- rotation of arm to palm-up position pronation- palm down circumduction- swinging arms in circles inversion- turning foot so sole is inward eversion- sole is out
  • 23. Elevation and depression- raising body part up or downAging and bones both bone and cartilage tend to deteriorate cartilage: chondrocytes die, cartilage becomes calcified osteoporosis; bone is broken down faster than it can be built bones get weak and brittle; tend to fracture easily
  • 24. Risk factors for osteoporosisInadequate calciumLittle weight-bearing exerciseDrinking alcohol, smokingBeing female: decreased estrogen secretion after menopauseSmall frameCaucasian or Asian ethnicity
  • 25. Skeleton and other systemsSkin makes vitamin D which enhances calcium absorptionSkeleton stores calcium for muscle contraction, nervous stimulation, blood clot formationRed marrow- site of blood cell formationCalcium levels regulated by parathyroid hormone and calcitonin kidneys (can help provide vitamin D) digestive system (can release calcium into blood
  • 26. Growth hormone regulates skeletal growth stimulates cell division in epiphyseal disks in long bonesGrowth stops when epiphyseal disks are converted to boneWhen excess growth hormone is produced in childhood→gigantismIn adulthood- acromegaly. Bones can’t grow but soft tissue can
  • 27. When muscle contracts, it shortens and causes movementSkeletal muscles attached to bones by tendonsInsertion- attachment to more movable boneOrigin- less movableFlexors and extensors act on the same joint to produce opposite actions
  • 28. Materials:2.SRJ “Medicine Today”, 20113.Anatomy and Physiology. S. Walner, 20004.Daily Strength. M. Promtone, 20103.