Bone Coverings

Question 1

Compact Bone - periosteum

Answer 1

• Is covered w/ a dual-layered membrane - Periosteum
• Covers all of the bone except parts enclosed in joint capsules
• Made up of an outer, fibrous layer + an inner, cellular layer

Function:

1. isolate bone from surrounding tissue;
2. provide a route for blood + nerve supply;
3. participate in bone growth + repair (inner layer)

Perforating fibres: collagen fibres of the periosteum

• Connect w/ collagen fibres in bone
• And w/ fibres of joint capsules, tendons + ligaments – where they attach to bone

Question 2

Compact Bone - Endosteum

Answer 2

• Endosteum on the inside….

An incomplete cellular layer:

• Lines the medullary (marrow) cavity
• Covers trabeculae of spongy bone
• Lines central canals
• Contains osteoblasts, osteoprogenitor cells, + osteoclasts
• Active in bone growth + repair