Cells
These cells found in the periosteum and endosteum are mitotically active
What are osteogenic cells?
Osteoblasts in the periosteum secreting bone matrix on the external surface is an example of what type of growth?
What is appositional growth?
What is an osteon?
What radiates from the lacunae, allowing osteocytes to connect with each other and the central canal?
What are canaliculi?
A small, rounded projection is called?
What is a tubercle?
When the blood Ca+ levels fall, this cell is activated by PTH to begin degrading bone
What are osteoclasts?
In endochondral ossification, the secondary ossification center appears where?
What are the epiphyses?
Forming the long axis of the bone, this shaft contains the medullary cavity
What is the diaphysis?
Running perpendicular to the long axis of the bone, these connect the blood/nerve supply of the medullary cavity to the central canals.
What are perforating canals?
This opening can be round or oval; very important for the passage of blood vessels and nerves
What is a foramen?
Secretes bone matrix that includes collagen and calcium-bind proteins
What are osteoblasts?
Mesenchymal cells clustering and differentiating into osteoblasts to form an ossification center is the first step of what?
What is intramembranous ossification?
What is formed by the bones of the skull, vertebral column, and rib cage?
What is the axial skeleton ?
What is osteoid?
A smooth, nearly flat surface that helps form joints
What is a facet?
Spidery shaped and occupying lacunae, these cells can act as stress or strain "sensors"
What are osteocytes?
As you grow taller, chondrocytes at the epiphyseal plate divide, hypertrophy, calcify and then are replaced by new bone. This is an example of what type of growth?
What is interstitial growth?
What anchors the periosteum to the under lying bone?
What are perforating/Sharpey's fibers?
Where do the main vessels serving the diaphysis enter the bone?
What is the nutrient foramen?
The only example of this projection is on the femur; large, blunt, irregularly shaped process
What is a trochanter?
These flat cells are found on surfaces where remodeling is not going on; they're thought to help maintain the matrix
What are bone lining cells?
A disease in which bone resorption outpaces bone deposit
What is Osteoporosis?
Just deep to the periosteum and just superficial to the endosteum, these extend around the entire circumference of the diaphysis
What are circumferential lamella?
A disc of hyaline cartilage that grows during childhood to lengthen the bone
What is the epiphyseal plate (growth plate) ?
A cavity within a bone, filled with air and lined with mucus membranes; humidifies air before it reaches the lungs
What is a sinus?