Chapter 11

• bones are living organs that contain bone tissue, cartilage, and connective tissue.
• Nerves and blood are found within bones, to support it;s activities
• Bones provides strength and flexibility
• Bones contain 65% mineral that provides it it's hardness
• Bones contain 35% organic structures for flexibility (collagen)
• Hydroxyapatite are mineral crystals around collagen that are designed to bear weight (calcium and phosphorous)
• Cortical bone makes 80% of skeleton, which is the outer surface of the bone
• Trabecular bone is the inside of the bone and makes up 20% of it,
• The trebacular bone has a fast turnover rate, it is sensitive to hormonal and nutritional differences
• Bone growth completes by age 18 in girls and age 21 in boys
• Bone modelling is complete by early adult hood, exercise and overweight increase bone thickness
• Bone remodelling is the breakdown of old bone tissue and the formation of new ones
• Bone density is the compactness of bones
• Peak bone density is when bones are at their strongest
• Resorption: surface of bones is broken down by osterclasts
• New bone matrix is then formed by osteoblasts, which can synthesize a new bone matrix by laying down collagen containing components of bone
• Hydroxyapatite crystalizes and packs together
• Bone resorption and formation are equal in young and healthy adults
• Resorption exceeds new bone formation after age 40, density begins to decrease
• High peak one mass is achieved through proper nutrition and exercise
• A stronger skeleton is protective against osteoperosis
• Calcium provides structures for bones and teeth
• Calcium assists with the acid base balance
• Calcium assists in the transmission of nerve impulses
• Calcium assists in muscle contraction
• Osteoporosis is a long term calcium deficiency
• Vitamin D is a fat soluable vitamin that is stored in the liver and adipose tissue
• Vitamin D can be synthesized by the body from exposure to UV rays from the run
• Vitamin D is considered a hormone, synthesized in one location and regulates activities in other parts of the body
• Fluoride is a trace mineral stored in teeth and bones
• Fluoride develops bones and teeth
• Fluoride combines with calcium and phosphor. to form fluorohydroxyapatite to form teeth
• Fluorosis is excess fluoride that stimulates protein content of tooth enamel and makes teeth porous
• Hydroxyapatite: mineral crystals around collagen to bear weight
• Hydroxyapatite components: calcium and phosphor
• Hydroxyapatite formation: influenced by the magnesium
• Osteoclasts break down bones which is stimulate by vitamin D
• Osteoblasts build bone that secretes osteocalcin, which is dependant on vitamin K
• Osteoporosis is the most prevalent disorder that affect bone health
• Osteoporosis is charatarized by low bone mass, bone tissue decay, fragile bones, and bone compaction