Bone formation, modelling and remodeling

Question 1

Define Ossification?

Answer 1

The production of bone. When bones grow/fuse

Question 2

What is bone made up of?

Answer 2

calcium phosphate, calcium carbonate, collagen and water

Question 3

What is collagen?

Answer 3

Elastic substance in bones, keeps bones strong

Question 4

How is compact bone formed?

Answer 4

Starts as cartilage

osteoblasts (bone forming cells, found in cartilage, releases osteoid and minerals)

Question 5

How is cancellous bone formed?

Answer 5

fibrous membrane
osteoblasts found in cartilage
releases osteoid into membrane and forms sponge-like bundle of fibres called trabeculae

Question 6

How do bones grow?

Answer 6

Epiphyseal plate is where growth begins. when growth is over it turns into an epiphyseal line.
Children/adolescents can damage plates by doing maximal lifts

Question 7

What is involved in bone remodeling

Answer 7

constant cycles of bone reabsorption and formation of new bone
controls reshaping/replacement of bone

Question 8

What are the cells that are involved in bone formation

Answer 8

both have multiple nuclei
Osteoblasts - secrete osteoid for bone growth. help to build bone
Osteoclasts - release acid/enzymes to remove old bone and reshape bone

Question 9

What happens with remodeling when you are younger vs when you are older

Answer 9

remodeling happens a lot when you are younger
remodeling decreases from age 35+
when you are 40+ 5-10% of bone is lost
Collagen is lost and bone becomes more brittle and pliable