Chp 6 bone remodeling &factors affecting bone growth
What are the three factors that contribute to normal bone metabolism?
Adequate intake of vitamins, minerals and sufficient levels of hormones
What are the two factors bone remodeling goes through?
Bone resorption and bone deposition
What are the 2 large amounts minerals needed for bone growth & remodeling ?
Calcium and phosphorus
Regarding bone growth, What is vitamin D used for?
Increaes the absorption of calcium from foods in the GI tract
During childhood, what hormones are most important to bone growth?
Insulinlike growth factors (IGFs)
What are the 3 smaller amounts of minerals needed for bone growth and development?
Magnesium,fluoride and manganese
How do osteoclasts work
Seals itself to the surface of bone at the endosteum or periosteum, excretes lysosomal enzymes(dissolves collagen &organic)and acids (dissolves bone material).Material endocytosis in cells and exocytosis on the opposite side
During puberty,what hormone causes dramatic effect on bone growth?
Sex hormones (estrogen & testosterone)
How do IGFs effect bone growth and development?
Stimulate osteoblasts, promote cell division at the epiphyseal plate and periosteum and enhance protein needed to build new bone
Regarding bone growth, What is vitamin A needed for?
Stimulates activity of osteoblasts
Regarding bone growth, What is vitamin K and B12 used for?
Synthesis of bone protein
Regarding bone growth, What is vitamin C needed for?
Synthesis of collagen
What is bone deposition?
The addition of minerals and collagen fibers to bone by osteoblasts
What is bone remodeling?
The ongoing replacement of old bone tissue by new bone tissue
What is bone resorption?
The removal of minerals and collagen fibers from bone by osteoclasts
How are osteoclasts able to create a seal when attaching to bone?
The ruffle boarders give it this capability