Exam 2 Review Notecards

Question 1

Bone Histology

Answer 1

Bone, osseous tissue- contains extracellular matrix that surrounds widely separated cells.
It is..
15% water
30% collagen fibers
55% crystallized mineral salts
Calcium phosphate- most abundant mineral salt

Calcification initiated by bone building cells (osteoblasts). Mineral salts are deposited and crystallize.

- Hardness- depends on crystallization of salts
- Flexibility- depends on collagen fibers

4 Types of Cells:

1. Osteogenic
- Undergo cell division, remaining cells turn into osteoblasts
2. Osteoblasts
- bone-building cells, synthesize ECM of bone tissue 
3. Osteocytes
- mature bone cells, exchange nutrients and waste with blood
4. Osteoclasts
- Release enzymes that digest mineral components of bone matrix, regulate blood calcium level

Blasts Build, Clasts Carve

Question 2

Osteon

Answer 2

repeating structural units.
osteons consists of a central canal with concentric lamellae (rings) with lacunae in between the rings which contains osteocytes, from the lacunae are canaliculi filled with ECF -canaliculi connect lacunae forming a system of interconnected canals-provides route for nutrients and oxygen to reach osteocytes.

Osteons —-> Concentric lamellae (rings) —-> lacunae —-> canaliculi —-> osteocytes

Question 3

Functions of Bone

Answer 3

1. Protection
2. Blood cell production
3. Assistance in movement
4. Support
5. Mineral homeostasis (storage and release)
6. Trigylceride storage (Yellow bone marrow)

Question 4

Vocab for bone

Answer 4

Diaphysis- main portion, shaft
Epiphyses- proximal and distal ends
Metaphyses- between diaphysis and epiphyses
Articular cartilage- thin layer of hyaline cartilage, forms articulation of joint, absorbs shock, reduces friction
Periosteum- attached by perforating fibers
Medullary cavity (marrow cavity)- minimizes weight of bone
Endosteum- thin membrane that lines medullary cavity