Cartilage and Bone Flashcards
What is the role of Connective Tissues
To provide structural, metabolic and defensive support for other tissues and organs
Describe the first 4 types of collagen and where they can be found in the body
Type 1 - thick bundles (bone)
Type 2 - thin, interwoven (cartilage)
Type 3 - delicate and branching (reticulin fibres)
Type 4 - meshwork forming (basement membrane)
What is the role of elastic fibres and what is their precursor
Role = stretch and resilience Precursor = tropoelastin
How does elastin form fibrils and where is it found
Forms fibrils with fibrillin that connects tropoelastin monomers together
Found in arteries, skin, lungs and cartilage (connective tissues)
What is the role of cartilage and what features of cartilage make it adapted for that
Structural role - solid but flexible, resists compression
What are the 3 kinds of cartilage
Hyaline
Elastic
Fibrous
What are chondroblasts and where are they found
Immature cells that form cartilage.
Found in perichondrium - A layer of dense irregular connective tissue that surrounds the cartilage of developing bone
What are chondrocytes and what do they do
Mature cells that maintain cartilage
Found in lacunae surrounded by cartilage
Where can hyaline cartilage be found
Trachae, bronchi, sternal ends of ribs, nasal septum and joints
What role does hyaline cartilage have in bone development
Forms as a model template for bones in development
What is the difference between elastic and hyaline cartilage
Similar to hyaline, but with the incorporation of large amounts of elastic fibres
Where can elastic cartilage be found
Outer ear, epiglottis and larynx
Describe the structure of fibrocartilage
Alternating layers of cartilage matrix and collagen fibres
Where can fibrocartilage be found in the body
Intervertebral disks, knee joint meniscus and symphysis pubis
What are the roles of bones
Structural, locomotion, supportive, protective, metabolic, highly organised and metabolically active
How can tooth loss affect the alveolar bone
Results in reduction of mechanical strain in alveolar bone and subsequent ridge resorption
What are osteocytes
mesenchymal, maintains bone and are mechanosensors
What are osteoblasts
Mesenchymal, secretes osteoid
What are osteoclasts
Hematopoietic, resorbs bone
What is the organic matrix of bone known as and what is it mainly composed of
Osteoid
90% collagen + non-collagenous proteins
What is the inorganic matrix of bone made up of
Calcium
Phosphorus
What is osteoid
Unmineralised Ground Substance
What is woven bone and describe its features
Formed first
Mechanically weak
Random organisation of collagen
What is lamellar bone and describe its features
Mature ‘remodelled’ bone
Layers of organised collagen
Mechanically strong
Can be compact or trabecular
How is lamellar compact bone organised
Organised into bony columns called osteons with central Haversian canals
What do Haversian canals do
Convey blood to the surrounding osteocytes
What is the periosteum
Vascular fibrocollagenous tissue that surrounds most of the outer surfaces of bones
How is lamellar trabecular/cancellous bone organised
In beams or spicules along lines of stress, strong but lightweight
How is blood supplied to lamellar trabecular/cancellous bone
no osteons, blood supply is from outer surfaces
What fills the spaces between trabeculae
bone marrow
Where in the bone can trabecular bone be found
In the medullary portion of the bone in the middle
What is an osteon
Lengthwise bony column in compact bone with central haversian canal
How is the osteon connected to the periosteum
Volkmann’s canals
What is the endosteum
Delicate tissue that lines canals and is continuous with the periosteum
What bone cells can be found in both the endosteum and periosteum
inactive osteoblasts
What are canaliculi
Tiny canals that connect osteocytes to their blood supply
