Functions of the musculoskeletal system: (6)
Mineral phase of bone:
Organic phase of bone:
Bone cells: osteochondral progenitor cells
Bone cells: Osteoblasts
Bone cells: osteocytes
Bone cells: Osteoclasts
Types of bone: (2)
- Trabecular bone
Bone and calcium:
- Body contains approximately 1Kg of calcium and 99% of that is bone
Calcium regulation: Parathyroid hormone
Vitamin D sources:
Vitamin D activation pathway: - 2 Reactions - Liver: cholecalciferol to ..... - Kidney: ...... to active vit D Regulated by the enzyme:
Actions of vitamin D:
Calcitonin:
- Opposes the effect of PTH
Regulation of low calcium levels:
- Calcium levels increase
Bone density:
Factors effecting bone density: (3 main)
- Availability of substrates . Ca intake, Ca absorption, PTH functionality - Physiological factors . Exercise, BMI, smoking - Biochemical factors . Hormones
Groups that require calcium supplementation:
- Lactose intolerance
Bone density after menopause:
Macroscopic bone structures: (2)\
- Appendicular: Limbs, pelvis, shoulders
Osteology:
Cortical bone: (4)
Cancellous bone: (5)
Haematopoiesis: