BONE GROWTH, REMODELING & REPAIR Flashcards
The _____ is the outer layer that covers the external surface
Periosteum
The _____ is the inner layer of tissue that covers the internal surface of bones
Endosteum
Steps of bone remodeling
- Osteocytes sense changes in forces on bone
- Osteocytes release chemical messages
- Chemical messages recruit and activate osteoclasts and osteoblasts
- Osteoclasts create tunnels into osseous tissue parallel to force
- Osteoblasts become osteocytes in new matrix and new osteon is formed
Which of the following relationships will promote the loss of bone density (an overall reduction of osseous tissue)?
More active osteoclasts and less active osteoblasts
What is the order of zones in the epiphyseal growth plate?
- Resting Zone
- Proliferating Zone
- Hypertrophic Zone
- Calcification Zone
In what Zone is there inactive stem cells in the growth plate?
Resting Zone
What is the proliferating zone?
It is where the stem cells divide to make chondrocytes creating a cartilage matrix (mitosis)
What happens to chondrocytes in the hypertrophic zone?
The enlarge then die, creating spaces in the matrix
What two cells are in the calcification (and ossification) zone and what do they replace cartilage with?
Osteoclasts destroy the cartilage matirx and osteoblasts lay down osseous tissue replacing cartilage with new bone
Which of the following cells types undergo rapid and extensive mitosis in the epiphyseal plate?
A) Chondrocytes
B) Osteocytes
C) Osteoclasts
D) Osteoblasts
Chondrocytes
In which of the following zones would you find active osteoblasts and osteoclasts?
Ossification zone
A disease that decreases the amount of collagen fibers in the matrix will result in which of the following symptoms?
Brittle bones
A disease that decreases the amount of calcium deposited in bone will have which of the following effects?
A) Bone will be more bendy and flexible than usual
B) Bone will be harder than normal
C) Bone will be more brittle than normal
D) Bone will be more dense than normal
Bone will be more bendy and flexible than usual
What is Interstitial Growth?
Growth in the length of our bones
Where does intersitial growth occur?
In the growth plate between the epiphysis (head) and diaphysis (shaft)
