Chapter 6 Flashcards
What is bone made up of?
Osseous tissue, cartilage, dense connective tissue, epithelium, adipose tissue and nervous tissue
What are the basic functions of the skeletal system?
- Support
- Protection
- Assistance in moving
- Mineral homeostasis (storage and release)
- Blood cell production
- Triglyceride storage
What does red bone marrow produce?
Red blood cells, white blood cells, platelets
What is hemopoiesis?
Hemopoiesis is the process when red bone marrow produces red blood cells, white blood cells, or platelets
What does yellow bone marrow do?
Stores triglycerides
What is a long bone?
A bone whose length is greater than its width
What parts does a typical long bone consist of?
- Diaphysis
- Epiphyses
- Metaphases
- Articular cartilage
- Periosteum
- Medullary cavaty
- Endosteum
Diaphysis
The bone shaft. the long, cylindrical, main portion of the bone
Epiphyses
The proximal and distal ends of the bone
Metaphyses
The regions between the diaphoresis and the epistasis contains epiphyseal (growth) plates
Epiphyseal (growth) plate
A layer of hyaline cartilage that allows the diaphysis of the bone to grow in length when it stops growing the cartilage in the epiphyseal plate is replaced by bone
Epiphyseal line
The cartilage in the epiphyseal plate that is replaced by bone is known as this
Articular cartilage
A thin layer of hyaline cartilage covering the part of the epiphysis where the bone forms an articulation with another bone this cartilage reduces friction and absorb shock at freely moveable joints
Periosteum
A tough connective tissue associated with blood supply composed of outer fibrous layer and an inner osteogenic layer attached to the underlying bone by perforating fibres
Perforating fibres or sharpies fibres
Six bundles of collagen that extend from the periosteum into the bone extra cellular matrix
Medullary cavity
A hollow cylindrical space within the dyphisis that contains fatty yellow bone marrow and numerous blood vessels minimizes weight of the bone
Endosteum
A thin membrane that lines the medullary cavity contains a single layer of bone forming cells in a small amount of connective tissue
Osseous tissue
Connective tissues with an abundant extracellular matrix
Hydroxyapatite
Calcium phosphate combined with another mineral salt calcium hydroxide which form crystals of hydroxyapatite
How is calcification initiated?
By bone building cells called osteoblasts
What’s it called when mineral salts which are deposited into the extra cellular matrix crystallize and the tissue hardens?
Calcification
What are the four types of cells that are present in bone tissue?
- Osteoprogenitor cells
- Osteoblasts
- Osteocytes
- Osteoclasts
Osteoprogenitor cells
Unspecialized bone stem cells derived from mesenchyme
undergo cell division resulting in osteoblasts
found along the inner portion of the Periosteum, in the endosteum, and in the canals within bone that contains blood vessels
Osteoblasts
Bone building cells
synthesize and secrete collagen fibres and other organic components needed to build the extracellular matrix
Osteocytes
Mature bone cells
main cells in the bone tissue and maintain its daily metabolism such as the exchange of nutrients and waste within blood
do not undergo cell division
Osteoclasts
Huge cells
concentrated in the endosteum releases powerful lysosomal enzymes and acids that digest the protein in mineral components of the underlying extracellular bone matrix
help regulate blood calcium levels
Compact bone tissue
Contains few spaces and is the strongest form of bone tissue provides protection and support and resist the stress is produced by weight and movement
What is compact bone tissue composed of?
Osteons
What do osteons consist of?
- Concentric lamellae
- Ostionic canal
What is the concentric lamellae?
Circular plates of mineralized extra cellular matrix of increasing diameter surrounding a small network of blood vessels and nerves located in the central canal
Lacunae
Small spaces between the concentric lamellae which contain osteocytes
Canaliculi
Radiate from the lacunae And are filled with extra cellular fluid connect lacunae with one another and with the central canals providing many routes for nutrients and oxygen to reach the osteocytes
Osteons in compact bone tissue are aligned in the same direction and are _______to the length of the diaphysis?
Parallel
Interstitial lamellae
Located between neighbouring osteons and are fragments of old osteons that have been partially destroyed during bone rebuilding or growth
Interosteonic canals
Blood vessels and nerves from the periosteum that penetrate the compact bone And connect the medullary cavity, periosteum, and central canals
What are the lamellae arranged around the entire outer and inner circumference of the shaft of a long bone?
Circumferential lamellae