the skeletal system by kristen jebulan and elisha espino february 27, 2014 period 3
TRANSCRIPT
Skeletal Organization:
The Axial Skeleton
Skull
Cranium
Face
Hyoid
Sternum
Vertebralcolumn
Ribs
Sacrum
Skeletal Organization:
The AppendicularSkeleton
ClavicleScapula
Humerus
Coxa Radius
Ulna
Phalanges
Carpals
Metacarpals
Femur
PatellaTibia
Fibula
TarsalsMetatarsals
Phalanges
Bone Function: Support/Protection• Give shape to structures• Provide support and
protection• Examples: bones of skull
protect eyes, ears, and brain; bones of lower limbs, pelvis, and backbone support body weight
Bone Function:Storage of Inorganic Salts• Calcium salts are released
from ECM into blood after osteoclasts are stimulated when blood is low in calcium
• Homeostatic mechanism• Maintains sufficient blood
calcium levels for muscle contraction, nervous impulse conduction, etc.
The Long BoneProximalEpiphysis
Distal epiphysis
Diaphysis
Articular cartilage
Articular cartilage
Spongy bone
Compact boneEndosteum
PeriosteumMedullary cavity
• Osteoblasts• bone-forming cells. Called
“osteocytes” when extracellular matrix (ECM) completely surrounds the osteoblasts.
• Osteoclasts• Large, multinucleated cells
that break down the calcified ECM. • Secrete an acid that dissolves
inorganic component of the calcified matrix
JointsFibrous• Dense connective
tissue• No movement
Cartilaginous • Hyaline
cartilage• Limited
movement
Synovial• Cartilage,
synovium, synovial fluid
• Free movement
Synovial Joint TypesBall-and-socket• All planes; rotation• Ball-shaped with
cup
Condyloid• Variety; no
rotation• Oval condyle and
elliptical cavity
Gliding• Sliding/twisting• Articulating
surfaces; flat/curved
Synovial Joint Types (con.)Hinge• Flexion and extension• Convex surface fits
into concave surface of other
Pivot• Rotation around central
axis• Cylindrical surface of a
bone rotates within a ring
Saddle• Variety of movement• Articulating surfaces
have both concave and convex regions
Bone DiseasesArthritis
• Inflammation in the joint that causes pain• Treatable, but not curable• Can originate from genetic makeup,
constant physical-demanding activity on joint, obesity, etc.
Osteoporosis • Bone become weak and are more likely to
break
• Treatable, but not curable
• Can originate from aging, smoking, drinking, low body weight, gender (women), medication use, etc.