Presentation on theme: " Support › Allows us to stand erect. Protection › Ribs protect the heart and lungs. Movement › Serve as attachment for skeletal muscles Storage."— Presentation transcript:
Support › Allows us to stand erect. Protection › Ribs protect the heart and lungs. Movement › Serve as attachment for skeletal muscles Storage › Mineral, including calcium Blood Cell Formation › hematopoiesis
Compact (dense) bone › Looks smooth and homogeneous Spongy (cancellous) bone › Composed of small needlelike or flat pieces called trabeculae. › Has a lot of open space.
Compact bone: › Filled with canals and passages for nerves and vessels. › Structural unit is the osteon or Haversian system.
Spongy Bone › Consists of trabeculae. › No osteons are present.
Diaphysis- shaft of the long bone. Consists of a collar of compact bone surrounding a medullary cavity. Epiphyses- ends Epiphyseal Line- remainder of the growth plate. (cartilage) Endosteum- thin membrane lining the medullary cavity. Contains osteoblasts and osteoclasts.
Red marrow is found in long bones and flat bones. This is the area where blood cell production takes place.
Some illnesses can only be cured with a bone marrow transplant. What do you think you know about this process?
Remodeling › Coordinated by packets of osteoblasts and osteoclasts called remodeling units. › In healthy adults, bone mass remains constant. › Controled by 2 loops 1. mechanical and gravitational forces 2. negative feedback hormonal mechanism. blood calcium release of PTH release of Ca from bone by osteoclasts.
Types of fractures. Phases of fracture healing.
Osteogenesis and ossification › Fetal skeleton is mostly hyaline cartilage. › Gradually replaced by bone and hardened. › Flat and irregular bones are formed by intramembranous ossification. › Long and short bones are formed by endochondral ossification.
Longitudinal › Growth at the epiphyseal plate by mitosis. › Grow in length. Appositional › Increases bone thickness. *Growth hormone released during infancy and childhood
Osteoporosis › Reduced by mass due to increased bone reabsorption. Osteomalacia/ Rickets › Bones do not have enough calcium, making them soft. › Caused by Vit. D deficiency. Paget’s Disease › Excessive and abnormal bone formation.
Flat long Short irregular
Two types of bone markings: › Projections (aka processes) that grow out from the bone › Depressions (cavities) that indent the bone
Condyle : Rounded articular projection Head : bony expansion on a narrow neck Facet : smooth, nearly flat articular surface head Facet
Ramus: Armlike bar of bone
Crest: Narrow ridge of bone (Line: smaller than a crest) Epicondyle: Raised area on or above a condyle
Tubercle: Small rounded projection Tuberosity: large rounded or roughened projection Trochanter: very large, blunt projection (only on femur)
Spine: Sharp, pointed projection Ex: sharp points on the throacic vertebrae.
Allow blood vessels or nerves to pass through. › Meatus: (me - A- tus) Canal or tube › Sulcus, Groove or Furrow: a shallow depression
Sinus: Cavity within a bone; filled with air and lined with mucous membranes Foramen: Round or oval opening Foramen Magnum
The spinal column contains 33 bones termed vertebrae. The spine has five regions. Region # of Vertebrae Body Area Abbreviation Cervical 7Neck C1 - C7 Thoracic 12Chest T1 - T12 Lumbar 5 or 6Low Back L1 - L5 Sacrum 5 (fused)Pelvis S1 - S5 Coccyx 3Tailbone None
Atlas (C1) › first cervical vertebra, C1. › supports the skull. › It looks different than other vertebrae. The Atlas is a ring- shaped bone. Axis (C2) › second cervical vertebra, C2. › It looks like a dull tooth and sticks upward into the ring of the Atlas. The dens or tooth extends up from the C2 and joins with the inside of the C1 ring. **The Atlas and Axis allow the head to turn from side to side.