Skeletal Organization Flashcards
What is the function of the skeletal system?
Supports the body and organs - framework of the body
Protection - enclosed the vital organ- the brain, spinal cord, heart and lungs
Movement - force placed on the skeleton by the skeletal muscles provides for locomotion
Blood formation - location of the red bone marrow that is the source of both red and white blood cells .
Reservoir for metabolic calcium - stores excess nutritional calcium and releases calcium into blood when needed.
What is the skeletal anatomy - which segments are seperated into two?
Axial Skelton - cranium, vertebral Column, thorax, hyoid bone. (Skull, spinal cord, jaw, chest)
Appendicular Skeleton - pectoral girdle (scapula and clavicle (clavicle bone and shoulder blade)
Pelvic girdle - innominate (pelvic) bones
Upper extremities - humerus, radius, ulna, carpals, metacarpals, phalanges (arm)
Lower extremities - femur, tibia, fibula , tarsals, metatarsals, phalanges (leg)
What are the types of bones?
Flat bones - cranial bones, facial bones, costae, sternum, scapula, ilium, ischium and pubis.
Short bones - laminar putter cortex, touch cancerous medulla.
Irregular bones - humerus, radius, ulna , metacarpals, femur , tibia, fibula, metatarsals, phalanges. Cancellous heads, haversain (compact) shafts, medullary cavity.
Irregular bones - mandible, vertebrae. Combinations of the above listed types.
Sesamoid bone - found imbedded in tendon. The largest patella.
What is a cancellous bone (spongey bone) tissue composition?
Spindle bone with large open, marrow-filled spaces. (Like a sponge)
Made up of spicules and trabeculae (helps bone resist stress)
Highly vascularized (blood vessels)
Marrow might be either red (hemopoietic) makes blood cells or yellow (adipose) stores energy
Haversian (compact bone)
One of the denses. Gives up calcium.
Composed of Dense Matrix of calcium hydroxyapatite, laid down on the concentric circles around Haversian canals.
Haversian (longitudal) and Volkmann (transverse) canals contain a nerve, artery and vein, which supple osteocytes. (Living for remodeling, supplied with a blood supply, they have canals.)
Osteocytes isolated within matrix in small lacunae.
https://courses.lumenlearning.com/wm-biology2/chapter/structure-of-bones/
Composition of osseous ecm - bone
65% of matrix by weight consists of inorganic salt calcium hydroxyapatite (calcium, phosphate, hydroxyl and other trace minerals)
The remaining 35% collagen tule 1 proteoglycans and several other bone specific proteins s that link the collagen to the salt.
Growth of bone (Intramembranous ossification)
Mesenchyme (embryonic connective stem cells) condense and form trabeculae (bone sheets). (Fetal development no true bones formation)
Osteoblasts (osteogenic cells) adher to the surface and lay down osteoid tissue. Inner layers become calcified, trapping some osteocytes. The outer layer (periosteum) remains uncalcified
The Outer layer immediately under the periosteum Remove as a compact layer (laminar bone,) while inner layers or acted on by osteoclasts to produce large spaces, forming cancellous phone
Central axis? Proximal , distal?
Primmal closer to central axil and distal further away
Describe what red bone marrow and yellow bone marrow is
Red bone marrow - hemopoietic (blood forming m) tissue. In children’s it is scarred mostly in the spongy bone. In adult it is primarily concentrated in the sternum and illX crest of the ilum.
Yellow bone marrow - fills the medullary cavity of long bones and replaces red bone marrow in the most of the cancellous bones of adults.
Do we see laminar cavity in short and flat bone?
No
What is the Process of growth of long bone
The process takes place primarily in the epiphyseal plates (metaphysics) of long bone, which separate the epiphysis form the diaphysis during the bone elongation in the children
A layer of chrondoblasts diet lay down the hyaline cartilage surrounded by a perichondrium. The perichondrium populated by chondrocytes, increasing the thickness of hyaline cartilage layer.
Eventually oseteoblasts replace the chondroblast and the cartilage is slowly by bone.
