skeletal system of human body an overview .ppt

overview of skeletal system of a human body

1. Copyright © 2010 Pearson Education, Inc.
DR ADILA ANWAR
SEKELETAL SYSYTEM

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Consist of :
•bone
•cartilage

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SKELETAL CARTILAGES
•Initially our skeleton is made up of cartilages
and fibrous membranes
•Gradually our skeletal cartilages are replaced
by bone
•Upon reaching adulthood the skeleton
becomes almost fully ossified
•Only a few cartilages remain in the adult
skeleton

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TYPES
•There are three types of cartilage tissue:
hyaline,
•elastic,
• fibrocartilage
•Each contains a matrix of jellylike ground
substance and fibers

5. Copyright © 2010 Pearson Education, Inc. Figure 6.1
Axial skeleton
Appendicular skeleton
Hyaline cartilages
Elastic cartilages
Fibrocartilages
Cartilages
Bones of skeleton
Epiglottis
Larynx
Trachea
Cricoid
cartilage
Lung
Respiratory tube cartilages
in neck and thorax
Thyroid
cartilage
Cartilage in
external ear
Cartilages in
nose
Articular
Cartilage
of a joint
Costal
cartilage
Cartilage in
Intervertebral
disc
Pubic
symphysis
Articular cartilage
of a joint
Meniscus (padlike
cartilage in
knee joint)

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Bones of the Skeleton
•Two main groups, by location
•Axial skeleton (brown)
•Appendicular skeleton (yellow)

7. Copyright © 2010 Pearson Education, Inc. Figure 6.1
Cartilage in
external ear
Cartilages in
nose
Articular
Cartilage
of a joint
Costal
cartilage
Cartilage in
Intervertebral
disc
Pubic
symphysis
Articular cartilage
of a joint
Meniscus (padlike
cartilage in
knee joint)

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Classification of Bones by Shape
•Long bones
•Longer than they are wide
•Short bones
•Cube-shaped bones (in wrist and ankle)
•Sesamoid bones (within tendons, e.g., patella)

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Classification of Bones by Shape
•Flat bones
•Thin, flat, slightly curved
•Irregular bones
•Complicated shapes

10. Copyright © 2010 Pearson Education, Inc. Figure 6.2

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Functions of Bones
•Support
•For the body and soft organs
•Protection
•For brain, spinal cord, and vital organs
•Movement
•Levers for muscle action

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Functions of Bones
•Storage
•Minerals (calcium and phosphorus) and growth
factors
•Blood cell formation (hematopoiesis) in
marrow cavities
•Triglyceride (energy) storage in bone cavities

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Bone Markings
•Bulges, depressions, and holes serve as
•Sites of attachment for muscles, ligaments,
and tendons
•Joint surfaces
•Conduits for blood vessels and nerves

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Bone Markings: Projections
•Sites of muscle and ligament attachment
•Tuberosity—rounded projection
•Crest—narrow, prominent ridge
•Trochanter—large, blunt, irregular surface
•Line—narrow ridge of bone
•Tubercle—small rounded projection
•Epicondyle—raised area above a condyle
•Spine—sharp, slender projection
•Process—any bony prominence

15. Copyright © 2010 Pearson Education, Inc. Table 6.1

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Bone Markings: Projections
•Projections that help to form joints
•Head
•Bony expansion carried on a narrow neck
•Facet
•Smooth, nearly flat articular surface
•Condyle
•Rounded articular projection
•Ramus
•Armlike bar

17. Copyright © 2010 Pearson Education, Inc. Table 6.1

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Bone Markings: Depressions and Openings
•Meatus
•Canal-like passageway
•Sinus
•Cavity within a bone
•Fossa
•Shallow, basinlike
depression
•Groove
•Furrow
•Fissure
•Narrow, slitlike opening
•Foramen
•Round or oval opening
through a bone

19. Copyright © 2010 Pearson Education, Inc. Table 6.1

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Bone Textures
•Compact bone
•Dense outer layer
•Spongy (cancellous) bone
•Honeycomb of trabeculae

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Structure of a Long Bone
•Diaphysis (shaft)
•Compact bone collar surrounds medullary
(marrow) cavity
•Medullary cavity in adults contains fat (yellow
marrow)

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Structure of a Long Bone
•Epiphyses
•Expanded ends
•Spongy bone interior
•Epiphyseal line (remnant of growth plate)
•Articular (hyaline) cartilage on joint surfaces

23. Copyright © 2010 Pearson Education, Inc. Figure 6.3a-b
Proximal
epiphysis
(b)
(a)
Epiphyseal
line
Articular
cartilage
Periosteum
Spongy bone
Compact bone
Medullary
cavity (lined
by endosteum)
Compact bone
Diaphysis
Distal
epiphysis

24. Copyright © 2010 Pearson Education, Inc. Figure 6.5
Compact
bone
Trabeculae
Spongy bone
(diploë)

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