Skeletal System Flashcards
Parts of the skeletal system
• bones
• joints
• cartilages
• ligaments
2 subdivision of the skeleton
- Axial skeleton
- Appendicular skeleton
• Support the body
• protects soft organs
• attached skeletal muscles allow movement
• store minerals and fats
• blood cell formation (hematopoiesis)
Skeletal system (functions of the bones)
Protect brain and spinal cord
Skull and vertebrae
Protects thoracic cavity organs
Rib cage
Store minerals and fats
• Calcium And phosphorus
• fat in the internal marrow cavity
The adult skeleton has
206 bones
Two basic types of osseous (bone) tissue
- Compact bone
- Spongy bone
Dense, smooth, and homogeneous
Compact bone
• small needle like pieces of bone
• many open spaces
Spongy bone
Bones are classified on the basis of shape into 4 groups
• long
• flat
• short
• irregular
• shaft enlarged ends
• contains mostly compact bone; spongy bone st ends
• all of the bones of the limbs (except wrist, ankle, and knee cap bones) are:
Long bones
Examples of long bones:
Femur and humerus
• thin, flattened and usually curves
• two thin layers of compact bone sandwich a layer of spongy bone between them
Flat bones
Examples of flat bones:
Most bones the skull, ribs, sternum
• generally cube-shaped
• contains mostly spongy bone with an outer layer of compact bone
• seasmoids bones are a type of bone that form within tendons (patella)
Short bones
Examples of short bones:
Carpals (wrist bones)
Tarsals (ankle bones)
• Do not fit other bones classification categories
Irregular bones
Examples of irregular bones:
Vertebrae and hip bones
• Diaphysis (shaft) and periosteum
Long bones anatomy
•Makes up most of bones length
• composed of compact bone
Diaphysis (shaft)
• outside covering of the diaphysis
• fibrous connective tissue membrane
• perforating (Sharpey’s) fibers secure periosteum to underlying bone
Periosteum
Composed mostly of spongy bone enclosed by thin layer of compact bone
Epiphysis (ends)
•< covers the external surface of the epiphyses
• made of hyaline cartilage
• decreases friction at joint surfaces
Articular cartilage
•Remnant of the epiphyseal plate
• seen in adult bones
Epiphyseal line
• flat pane of hyaline cartilage seen in young, growing bone
• causes lengthwuse growth of a long bone
Epiphyseal plate
• Lines the inner surface of the shaft
• made of connective tissue
Endosteum
• cavity inside the shaft
• contains yellow marrow (mostly fat/ in fats
• contains red marrow for blood cell formation in infants until ages 6 or 7
Medulla cavity
Bones of attachment for muscles, tendons, and ligaments
• passages for nerves and blood vessels
Bone marking
Grow out from the bone surface
Projection or processes
Indentations
• terms often begin with F
Depression or cavities
• composed of small, needle-like pieces of bone call _______ and open spaces
Trabeculae
Nature bone cells situated in bone matrix
Osteocytes
Cavities in bone matrix that house osteocytes
Lacunae
Concentric circles of lacunae situated around central (haversian) canal
Lamellae
• Opening in the center of an osteon
• runs leghtwise through bone
• carries blood vessels and nerves
Central ( harvesian)canal
A unit of bone containing central canal and matrix rings and structural and functional unit of compact bone
Osteon (haversian system)
•Tiny canals
• radiate from the central canal to lacunae
• form a transport system connecting all home cell t a nutrient suppy
Canaliculi
• canal perpendicular to the central canal
• carries blood vessels and nerves
Perforating (volkmanss) canal
Is the process of bone formation
Ossification
(bone- forming cells) cover hyaline cartilage model with bone matrix
Osteoblasts
The enclosed cartilage is digestive away, opening up a medullary cavity
Fetus
Formed continuously on the external face of these two cartilage
New cartilage
Is broken down and replaced by bony matrix
Old cartilage
Bones growth in width
Appositional growth
• release when calcium ion levels in blood are low
• activates osteoclasts
• osteoclasts break down bone and release calcium ions into the blood
Parathyroid hormone (PTH)
(high blood calcium levels) prompts calcium storage to bones by osteoblasts
Hypercalcemia
Bones are manually coaxed into position by physicians hands
Closed reduction
Bones are secured with pin wires during surgery
Open reduction
Healing times of bone fractures is.
6-8 weeks
(blood-filled swelling, or bruise) is formed.
Hematoma
Cartilage matrix, bony matrix, collagen, fibers splint the broken bone
Fibro cartilage callus forma
Osteoblasts and osteoclasts migrate in
Bony callus replaces the fibrocartilage callus
Repair of bone fractures involves 4 major events:
• hematoma
• fibrocartilage calus forms
•bony callus replaces the fibrocartilage callus
• bone remodeling occurs in response to mechanical stresses
