Physiology: The Skeletal System Flashcards
What structure of bones is the Diaphysis
▪ the long main portion of the bone▪a.k.a. body, shaft
What bone structure is the Epiphyses ▪sing. epiphysis, adj. epiphyseal?
▪ the ends of the bone
what region of the bone is the Metaphyses▪sing. metaphysis?
the regions between the diaphysis and the epiphyses
▪ contains the epiphyseal growth plate/epiphyseal line
What and where is the Epiphyseal Growth Plate?
▪ a cartilagenous area within the metaphysis of a growing bone
▪ once growth stops, what remains is the epiphyseal line
A thin layer of hyaline cartilage covering the epiphyses?
Articular Cartilage
what is Periosteum?
-a tough CT covering that surrounds bone
▪well vascularized and innervated
what does Periosteum do/is for?
▪it protects, nourishes and heals bone
▪it is an attachment for tendons and ligaments
▪outer layer is tough and supportive/protective
▪inner layer has bone forming cells
what is bone?
Connective tissue
Bone Structure: What is the Medullary Cavity a.k.a. marrow cavity?
▪the space within the diaphysis that contains:
1) red marrow (for blood cell formation)
2) yellow marrow (for fat storage)
what is bone made of/matrix?
25% water
25% collagen
50% mineral salts
what are osteoblasts?
bone building cells (and differentiate into osteocytes)
what are osteoclasts?
bone “eating” cells
what are osteocytes?
mature bone cells
what is an osteoprogenitor?
- cells that are active during normal growth, healing and cyclical bone replacement
- they differentiate and turn into osteoblasts
what are the two bone types?
spongy and compact
structure of compact bone contains?
- Osteons a.k.a. Haversian systems
- Central (a.k.a. Haversian) canal
- Concentric Lamellae
- Lacunae, sing. (lacuna)
- Canaliculi
- Volkmann’s Canals a.k.a. transverse perforating canals
a hole through the centre of the osteon through which blood and lymphatic vessels run
Central (a.k.a. Haversian) canal
rings of hard, calcified bone matrix around the central canal:
Concentric Lamellae
what is the Lacunae, sing. (lacuna)?
▪spaces between the rings▪in the lacunae are osteocytes (little “lakes”)
what are Canaliculi?
▪small channels sticking out (in all directions) from the lacunae▪filled with extracellular fluid
▪allows osteocytes to communicate
Volkmann’s Canals a.k.a. transverse perforating canals?
▪holes which run transversely to connect the inner and outer portions of the bone
Spongy bone contains:
trabiculae, which contain osteocytes in lacunae connected by canaliculi
periosteal arteries enter the diaphysis at multiple points (Volkmann’s canals) to supply:
the periosteum and outer compact bone
