Bones Flashcards
What is the difference between an osteoblast and an osteocyte?
An osteoblast is an immature bone cell
An osteocyte is a mature bone cell
What is the matrix in bone composed of?
25% protein fiber, 25% water, 50% crystallized mineral salts
What is the job of an osteoblast? An osteocyte?
An osteoblast lays down bone
An osteocyte maintains bone
Where does the hardness of bone come from? Where does it’s strength and flexibility come from?
Mineral salts and protein fibres
What are the 4 main types of cells in red bone marrow?
RBCs
WBCs
Adipocytes
Fibroblasts
What does an osteoclast do?
An osteoclast is a cell that dissolves bone
What is an open fracture?
A fracture where the bone protrudes
What is a comminuted fracture?
A fracture where the bone splinters
What is a green stick fracture?
A fracture where one side of the bone is broken and one side is bent
What is an impacted fracture?
A fracture where one side is driven into the other side
What is a pot’s fracture?
A fracture of the far end of the fibula
What is a Colles’ fracture?
A fracture of the far end of the radius and displaced posteriorly
What is a stress fracture?
A microscopic fissure(s) in bone caused by repeated stress (ie running, jumping, osteoporosis)
Where is 99% of the body’s calcium stored?
In the bones
Which hormone causes osteoclast activity to increase resulting in less calcium in bone and more in the blood?
Parathyroid
Which hormone causes osteoclast activity to decrease resulting in more calcium in bone and less in blood?
Calcitonin
What is the effect of mechanical stress on bone?
It lays down more bone
Why is bone resorption more marked in women?
Because of the reduction in sex hormones after menopause
What is the condition in which bone resorption is greater than bone deposition?
Osteoporosis
What causes rickets?
Failure of the bones to calcify
What is another name for adult rickets?
Osteomalacia
What causes osteoarthritis?
Mechanical stress wearing down cartilage
What causes rheumatoid arthritis?
Autoimmune inflammation-
WBCs attack the body’s own cells
What causes gout?
Sodium urate crystals
