Specialized connective tissue Flashcards
specialized form of fibrous connective tissue
cartilage
cartilage is _ and contains _ embedded in ECM that allow the exchange of nutrients and waste
avascular
chondrocytes
cartilage functions
support soft tissues and guide the development and growth of long bones
3 types of cartilage
hyaline, elastic, and fibrocartilage
hyaline cartilage location
articular ends of long bones in adults, walls of respiratory system, and the ventral ends of ribs
hyaline cartilage matrix has homogeneous, amorphous ground substance with _aggregates and _ embedded in _
proteoglycan
chondronectin
type II collagen
proteoglycan aggregates include
chondroitin sulfate and hyaluronic acid
area adjacent to chondrocytes that is poor in collagen but rich in gylcosaminoglycans
territorial (capsular) matrix
territorial matrix is basophilic and metachromatic and stains more intensely with PAS stain than
interterritorial (intercapsular) matrix
layer of dense irregular connective tissue that surrounds hyaline cartilage except at articular surfaces
perichondrium
perichondrium consists of
outer fibrous layer containing type I collage; also contains inner cellular layer containing chondrogenic cells (source of new cartilage cells)
perichondrium provides
blood supply for the avascular cartilage
mature cartilage cells embedded in lacunae in the matrix
chondrocytes
chondrocytes arise from _ into _, which produce cartilage matrix
chondrogenic cells
chondroblasts
officially called chondrocytes when
the cells are totally surrounded by matrix
chondrocytes may occur in groups of 2-8 cells called
isogenous groups
elastic cartilage has perichondrium like hyaline cartilage; matrix contains
network of elastic fibers (gives a yellowish color)
elastic cartilage is located
where flexible support is required (external ear, Eustachain tube, epiglottis)
fibrocartilage has no
perichondrium
fibrocartilage has properties
between dense connective tissue and hyaline cartilage
fibrocartilage has thick bundles of
type I collagen fibers
fibrocartilage is found
where support and tensile strength are needed with hyaline cartilage or fibrous tissues
fibrocartilage is commonly found at
articular disks
fibrocartilage is easily confused with
dense regular connective tissues
_ is aspecialized connective tissue with a _ ECM with osteocytes
bone
calcified
bone has _% of body calcium
99
bone is a dynamic tissue
undergoes shape change and absorption/reabsorption
bone matrix inorganic (calcified) portion is made of
calcium phosphate, bicarbonate, citrate, magnesium, potassium, and sodium
bone matrix consists primarily of
hydroxyapatite crystals
bone matrix organic portion is made primarily of
type I collagen
ground substance of organic portion of bone matrix contains
chondroitin sulfate and keratan sulfate
(immature, woven bone): first bone formed in fetal development and bone repair
primary bone
(mature, lamellar bone)
secondary bone
secondary bone has 2 types
compact bone (dense, outer portion) and spongy bone (interior meshwork of trabeculae)
compact bone is organized with _ below the periosteum and _ adjacent to the marrow cavity
outer circumferential lamellae
inner circumferential lamellae
rest of bone is organized around
Haversian canal systems (osteons)
osteons are connected to each other by
Volkmann’s canals
layers of noncalcified CT covering bone on external surfaces
bone periosteum
bone periosteum has a _ inner layer
cellular (osteogenic)
_ attach the periosteum to the bone
Sharpey’s fibers (type I collagen)
bone periosteum distributes _ to bone
blood vessels
thin specialized connective tissue
endosteum
endosteum function
lines marrow cavities and is a source of osteoprogenitor cells and osteoblasts for bone growth and repair
inner layer of periosteum and endosteal cells that line marrow cavity; can differentiate into ostoblasts
osteoprogenitor cells
secretes collagen and ground substance and osteoid (unmineralized bone)
osteoblast
osteoid regulates
mineralization of bone
maintain bone matrix by being able to synthesize and resorb matrix; reside in lacuna; communicate with other osteocytes and osteoblasts via processes that extend through canaliculi
osteocyte
multinucleated cell that can actively resorb bone and is acidophilic
osteoclast
depression in bone created by osteoclast; cell seals off area, acidifies and secretes acid hydrolases to resorb bone
Howship’s lacuna
decrease in bone mass
osteoporosis (occurs primarily in old age)
due to calcium deficiency in adults
osteomalacia (may be severe in pregnancy)
osteomalacia is characterized by _ of newly formed bone and _ of calcified bone
deficient calcification
decalcification
bone remodeling is not functioning properly leading to enlarged, brittle bone
Paget’s disease: osteitis deformans
osteomalacia in children is called _; characterized by deficient calcification in newly formed bone
rickets
excess pituitary growth hormone in adults leading to very thick bones in the extremities and facial skeleton
acromegaly
