Skeletal System Flashcards
Diaphysis
Long part of the bone
What are the 6 functions of the skeletal system?
Support, protection, assistance in movement, mineral homeostasis, blood cell production, triglygeride storage
Epiphysis
Distal and proximal ends
Articular cartilage
Covers epiphysis-protects where bones meet
Periosteum
Outside surface
Medullary cavity
Where marrow is found
Endosteum
Thin membrane inside bone
What is bone matrix made of?
25%water
25%collagen
50%minerals
Osteogenic
Only bone cells who divide- make osteoblasts
Osteoblasts
“Bone builders” secure collagen and initiates calcification
Osteocytes
Mature bone cells
Osteoclasts
Release enzymes to digest protein and minerals in matrix
Characteristics of Compact Bone
80% of skeleton
Arranged in OSTEONS
Provides protection support and resists stress
Characteristics of spongy bone
20% of skeleton
Composed of TRABICULLAE
Short and irregular bones
What is the difference between osteon and trabiculae?
Osteons are circular structures with the blood flowing in the middle
Trabiculae are porous structures that can absorb impact well
What indicates unhealthy bones in a bone scan?
Bones absorb radioactive tracers such as barium that make bones show up in the bone scan
Too dark or splotchy =increased metabolism = likely cancerous cells
Too light = decreased metabolism likely degenerative bone disease
Axial skeleton
Head, neck, trunk/spinal cord
Appendicular skeleton
Upper and lower limbs, pectoral girdle, pelvic girdle
What bone doesn’t articulate?
The hyoid, it’s a build up of cartilage that attaches the muscles of the mouth.
What is the function of the sinus cavity?
Allows air to pass and make mucus drain
What are fontanels? Why do they exist? How long do we have them?
Areas of cartilage connecting skull bones, “soft spots” on babies they fuse between ages 1-2
Interstitial growth
Length
Appositional growth
Width
Endochondral growth
Bones starting to develop in babies mostly cartilage, grows with the epiphyseal plate
