Download Skeletal System Lecture File

Skeletal System
Make no bones
about it.
What do bones do for you?
• Support & anchor soft tissue.
• Movement – muscles pull on bones to move
the body & its parts.
• Protection of soft, delicate organs.
• Formation of blood cells in red marrow inside
of bones.
• Storage of energy & minerals.
Axial
Appendicular
Bones
Bone Tissue
Two types of bone
tissue
1. Compact Bone- dense,
uniform and looks smooth.
2. Spongy Bone – composed
of small needlelike pieces
of bone and lots of open
space - allows for structure
and support with little
weight.
Bone Groups
1. Short bone- cubeshaped and contain
mostly spongy bone ex: wrist & ankle
2. Long Bones – longer
than wide w/ a shaft and
heads at both ends
-mostly compact bone,
contain both red and
yellow marrow. - ex:
femur, radius
3. Flat bones – thin, flattened,
usually curved
- 2 thin layers of compact bone
sandwiching a layer of spongy
bone & red marrow. - ex: skull,
ribs, sternum, scapula
4. Irregular bones – odd-shaped
bones not in the other groups ex: vertebrae & pelvis
Bone Groups
Bone
Anatomy
Parts of Bones:
A. Diaphysis – shaft of long bones
B. Epiphysis – ends of long bones
C. Periosteum – tough membrane covering bone, supplies it w/ blood vessels & nerves
Bone Marrow:
A. Red marrow – makes blood cells, found in spaces of spongy bone.
B. Yellow marrow – stores energy (fat), found in cavity in shaft of long bones, can convert to
red marrow if needed.
Compact Bone Structure
• Rings of mineral crystals (lamellae)
• Embedded with bone cells (osteocytes)
• Surround tubes containing blood vessels and nerves (Haversian
canals)
Compact Bone Structure
Joints
Fixed
Pivot
Saddle
Semimovable
Connective Tissue
Ligaments – connect bone to bone at a joint.
Tendons – connect muscle to bone, allows muscle to pull on bone &
move it.
Cartilage – often between bones at a joint, cushions & protects the ends
of bones from friction & wear.
* Synovial fluid – (* NOT A TISSUE – NO CELLS) lubricates & protects ends
of bones that are under pressure.
Bone Growth
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•
•
•
Ossification – cartilage converted into bone via mineralization by osteocytes.
Growth (Epiphyseal) Plates produce new cartilage cells toward center of bone.
Ends of bone are pushed outward, bone elongates.
Ossification occurs as cartilage cells toward center of bone are converted into
bone.
Bone Growth
Growth of Long Bones
Arthritis - Painful
inflammation (swelling) of
joints.
1. Osteoarthritis – agerelated, cartilage covering
ends of bones gets thin &
rough, bones rub together.
2. Rheumatoid arthritis –
immune system attacks
joint tissue.
Osteoporosis – loss of bone
mass that causes bones to
weaken and break easier.
Bone Disorders