BIOL 319 Exam 2: Long Bones Summarized/Bone Cells

How is the composition of diaphysis?

mainly compact bone

some trabecular 

How is the composition of the metaphysis and epiphysis?

mainly cancellous bone

some cortical bone

How do central canals run?

Haversian canals run straight up and down

Where do blood vessels first associate with in bone?

the periosteum

What's another name for the perforating canal?

volkmann

How many layers does the periosteum have?

2

outer: thick 

inner: births osteoblasts 

Why is the outer layer of the periosteum so thick?

tendons and ligaments attach to it

What are the 4 kinds of bone cells?

osteoprogenitors

osteoblasts 

osteoclasts 

osteocytes 

What are osteoprogenitors similar to?

cells in the stratum basale: both are mitotically active and have stem cells

When osteoprogenitors divide, what can they become?

osteoblast or chondroblast or another osteoprogenitor

Where can you find osteoprogenitors?

the periosteum and endosteum

What are the osteoblasts doing?

making bone matrix: first organic then inorganic

What is the organic matrix called, and its composition?

osteoid: mainly collagen

After the organic matrix, what do osteoblasts do?

secretes solution that lowers the solubility of calcium and phosphate: makes crystals

What is calcium/phosphate crystal formation an example of?

positive feedback loop

What is the calcium phosphate crystals known as?

the inorganic matrix

When osteoblasts have fufilled their purpose, what happens?

make a bony matrix around itself: now an osteocyte

Where/what are osteocytes?

in lacunae

maintains bone matrix 

Where are osteoclasts born from?

hematopoietic tissue

How are osteoclasts made?

from tons of WBCs fusing together