Histology of Bone - BM5 NLM1

HideShow resource information
What is bone?
A solid, mineralised, vascular connective tissue
1 of 37
In broad terms, bone tissue consists of four elements. Whatare they?
Periosteum, Endosteum, Bone matrix, Bone cells
2 of 37
What is the Periosteum?
A layer of dense, vascular connective tissue that covers the outer surface of bone (apart from articulating surfaces)
3 of 37
True or false: The Periosteum contains some bone stem cells and hence is important for bone growth and repair?
True
4 of 37
True or false: The Periosteum forms the site of anchorage of tendons & ligaments?
True
5 of 37
Whatis the Endosteum?
A layer of bone stem & forming cells that line the bone cavities and are important for bone growth, remodelling & repair
6 of 37
What two substance make up the extra-cellular bone matrix, and in what approximate ratio?
Osteoid (30%), Inorganic Minerals (70%)
7 of 37
What makes up Osteoid?
Mainly collagen type I embedded in a ground substance of proteoglycans, glycoproteins & water
8 of 37
What makes up the majority of the inorganic minerals of the bone ECM (hint: aka Hydroxyapatite crystals)?
Calcium phosphate complexes
9 of 37
What is the main function of the inorganic minerals in the bone ECM?
Binds to and mineralises the Osteoid
10 of 37
Whatare osteoprogenitor cells?
Bone stem cells
11 of 37
What are Osteoblasts?
Bone-forming cells that secrete and mineralise the Osteoid
12 of 37
Where are Osteoblasts located?
Periosteum & Endosteum only
13 of 37
Where are Osteoprogenitor cells located?
Periosteum & Endosteum only
14 of 37
What are Osteocytes?
Mature Osteoblasts that are non-dividing, oval, flattened, and located individually in lacunae in the bone ECM
15 of 37
What is the main role of Osteocytes?
To maintain the bone ECM
16 of 37
What is the name of the long processes that eminate from Osteocytes?
Canaliculi
17 of 37
What is the role of canaliculi?
To keep neighbouring Osteocytes in contact via gap junctions
18 of 37
What are Osteoclasts?
Large, motile, multinucleated cells of bone marrow origin
19 of 37
What is the function of Osteoclasts?
Bone resorption
20 of 37
What do Osteoclasts secrete?
Organic acids & proteolytic enzymes
21 of 37
Where are Osteoclasts located?
On the inner bone surfaces of eroded sites (Howship's lacunae)
22 of 37
True or flase: Bone remodelling is the reorganisation of bone structure by a balanced process of resorption and deposition of ECM?
True
23 of 37
True or false: bone remodelling is highly active in the young but negligible in adults?
True
24 of 37
Cortical bone forms what layer(s)?
The outer layer of long bone & outer plate of flate bone
25 of 37
True or false: the outer surface of cortical bone is covered by periosteum and the inner layer is lined by the endosteum?
True
26 of 37
Cortical bone is primarily composed of what?
Lamellar/mature bone tissue
27 of 37
The lamellar tissue that makes up cortical bone is arranged in Haversian Systems/Osteons. What are Osteons?
Parallel cylindrical units composed of central 'Haversion canals' surrounded by concentric osetocytes
28 of 37
What do Haversion canals carry?
Blood vessels & nerves only
29 of 37
What are Volkmann's canals?
The connecting systems between Haversion canals, bone cavities & the periosteum
30 of 37
True or false: Cancellous/trabecular bone consists of lamellar bone & remodelled osteons arranged into bony plates that occupy the central cavity and bridge the cortical bone?
True
31 of 37
True or false: in cancellous/trabecular bone, the density of the trabeculae varies in order to provide maximum strength?
True
32 of 37
What covers the surfaces of trabeculae?
Endosteum
33 of 37
What is contained in the bone cavities?
Bone marrow, vessels & nerves
34 of 37
In adults, most bone marrow in bone cavities is what?
Yellow marrow
35 of 37
Intramembranous ossifcation occurs in which fetal bone type?
Flat bones
36 of 37
Endochondral ossification occurs in which type of fetal bone?
Long bones
37 of 37

Other cards in this set

Card 2

Front

In broad terms, bone tissue consists of four elements. Whatare they?

Back

Periosteum, Endosteum, Bone matrix, Bone cells

Card 3

Front

What is the Periosteum?

Back

Preview of the front of card 3

Card 4

Front

True or false: The Periosteum contains some bone stem cells and hence is important for bone growth and repair?

Back

Preview of the front of card 4

Card 5

Front

True or false: The Periosteum forms the site of anchorage of tendons & ligaments?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Medicine resources:

See all Medicine resources »See all Histology resources »