Blood Formation, Growth, and Remodelling Flashcards
What are osteocytes specifically?
Mature bone cells
Where can osteocytes be found?
Within the bone matrix cavities
How many phases is ossification composed of?
Two major phases
What are osteoblasts?
Bone-forming cells
How is the natural process of bone formation described?
Hardening of the muscular tissue into bony substance
What happens when blood calcium levels drop below homeostatic levels? (2)
- The parathyroid glands release hormones into the blood
2. The hormones activate osteoclasts to break down bone matrix and release calcium ions into the bone
Define: osteoclasts
Giant, bone-destroying cells
Where is calcium deposited if the blood calcium level is too high and what is this condition called? (2)
- Calcium is deposited into the bone matrix as hard calcium salts
- Hypercalcemia
What is rickets and what causes it? (2)
- Disease in children where the bones fail to calcify
2. Lack of calcium and vitamin D
What happens when one has rickets? (2)
- The bones soften
2. Weight-bearing bones bow
List the 6 types of bone fractures and their general descriptors . (6)
- Comminuted → breaks into many pieces
- Compression → bone is crushed
- Depressed → bone is pushed inward
- Impacted → bone ends are forced into each other
- Spiral → ragged breaks occur when excessive twisting forces are applied
- Greenstick → incomplete break (like a young tree stick)
What are the traits of bone that are commonly comminuted?
Old, brittle bones
What are the traits of bone that are commonly compressed?
Osteoporotic bones in older population
What is an example of a depressed bone fracture?
Skull fracture
What are the traits of bone that receive greenstick fractures?
Young, flexible bones such as those in children
