Human anatomy and kinathropometry part 1 condensed Flashcards
Functions of periosteum?
Isolate bone from surrounding tissues Provide a route for circulatory and nervous supply Participate in bone growth and repair
What is endosteum?
An incomplete cellular that: Lines the marrow cavity Contains osteoblasts, osteoprogenitor cells and osteoclasts Is active in bone growth and repair
What is an osteon?
Osteocytes arranged in concentric lamellae around a central canal containing blood vessels
What do osteoblasts do?
Make and deposit components of bone extracellular matrix Eventually become surround calcified bone and then they become osteocytes
What do osteoclasts do?
Degrade and resorb bone for remodelling, by secreting acids and protein-digesting enzymes Dissolve bone matrix and release stored minerals = osteolysis
What do osteocytes do?
“watcher cells”, Sit in bone and monitor current status, and help repair damaged bone
What is an osteoid?
Unmineralized bone matrix composed of proteoglycans, glycoproteins and collagen, becomes calcified later
Where do you find osteocytes?
In matrix only (in the ring of bone)
Where do you find osteoblasts and osteoprogenitor cells?
Periosteum + Endosteum
Where do you find Osteoclasts?
In endosteum only
What do osteoprogenitor cells do?
They are mesenchyme stem cells that divide to form osteoblasts Are located in inner layer of periosteum Assist in fracture repair
How is homeostasis involved in bones and what happens if it isn’t maintained?
Bone building by osteocytes and -blasts, must balance the bone recycling from osteoclasts Higher resorption than formation leads to weaker bones
Life cycle of bone cells?
Osteoprogenitor cells to osteoblasts to osteocytes Osteoclasts are related to macrophages
What does red bone marrow do?
Produce red blood cells, platelets and white blood cells
What does yellow bone marrow do?
Produces fat, cartilage and bone
What us endochondral ossification and what are the names of all the steps?
Process by which bone tissue is created Formation of bone collar Cavitation Invasion Remodelling Ossification Elongation
In Endochondral ossification describe the step of bone collar?
Blood vessels grow around the edges of the cartilage Cells in the perichondrium (the connective tissue that envelops cartilage where it is not at a joint.) change into osteoblasts Producing a layer of superficial bone which will continue to grow and become compact bone
In Endochondral ossification describe the step of cavitation?
Chondrocytes in the centre of the hyaline cartilage of each bone model: Enlarge Forms struts and calcify Die, leaving cavities in cartilage
In Endochondral ossification describe the step of invasion?
Periosteal bud ( vascular connective tissue bud from the perichondrium) brings blood vessels into the cartillage Bringing osteoblasts and osteoclasts Spongy bone develops at the primary ossification centre
In Endochondral ossification describe the step of remodelling?
Remodelling creates a marrow cavity Bone replaces cartilage at metaphyses (end border if diaphysis) Diaphysis elongates
In Endochondral ossification describe the step of ossification
Capilaries and osteoblasts enter the epiphyses (top of the bone) Creating secondary ossification centres
In Endochondral ossification describe the step of elongation?
Epiphyses fill with spongy bone, but cartilage remains at 2 sites -ends of bones within the joint cavity = articular cartillage -cartillage at the metaphysis = epiphyseal cartillage (plate)
What are the 4 steps for the healing of a bone fracture?
Hematoma formed (bleeding)
Soft callus
Bony callus
Remodelling
What is the plane of movement called sagittal represent?
If someone was cut in half splitting their pecs in half
