Osteogenesis and Joints Flashcards
Which of the rolling is not a characteristic of fibrocartilage?
A.) Type II Collagen
B.) not surrounded by perichondrium
C.) Found in intervertebral discs
D.) Increased collagen in the matrix
E.) neither A nor B are characteristics of Fibrocartilage
A.) Fibrocartilage does not have Type II collagen it has Type I
Which of the following is not part of a Haversian system? A.) Periosteum B.) Lacunae C.) Lamellae D.) Volkmann Canals E.) Canalciuli
A.) Periosteum
Parathyroid hormone stimulates osteoblasts to secrete/express which of the following? A.) Osteoprotegerin B.) M-CSF C.) RANKL D.) All of the Above E) Only B and C
E.) only B and C
What signals control the aggregation of mesenchymal cells
Wnt, Hedghog, FGF, TGF-Beta
what is a blastema
Osteoblasts that are trapped by osteoid, which they secreted
Trapped osteoblasts are called what
Osteocytes
Mineralization of cartilage occurs via _______
Calcium ions
Calcification is a form of ___________ but is not a ossification
mineralization
Osteoblasts are derived from what kinds of cells
Mesenchymal cells
In intramembraneous bone formation the primary ossification center becomes a ______
trabecula
Numerous trabeculae fuse together to form what
Spongy bone
In intramembraneous bone formation osteoblasts form an epithelial-like covering over the surface of primary bone tissue and can secrete more _______ on the surface
Osteoid
In intramembranous bone formation osteoid includes ______ and _____ proteins
Collagen I and non-collagen
The initial bone formed in intramembraneous bone formation is _____
Woven bone
In Woven bone the collagen fibers are arranged ______
randomly
As collagen fibers become aligned the bone becomes
Lamellar
What is diploe
Layer of spongy bone that is enclosed by two layers of compact bone
What is it called when Lamellae become symmetrically arranged around a blood vessel forming an osteon
Haversian system
Explain Intramembraneous ossification
- ) Mesenchymal cells aggregate without a cartilage intermediate (controlled by patterning signals form polypeptides of the Wnt, hedgehog, fibroblast growth factor, and transforming growth factor- beta families)
- ) Mesenchymal cells differentiate into osteoblasts. a bone blastema is formed. Osteocytes within the core of the blastema are interconnected by cell processes forming a functional syncytium. Osteoblasts line the surface of the bone blastema
- ) Bone matrix (osteoid)- is deposited by osteoblasts. Later, Ca2+ transported by blood vessels, is sed in the mineralization process and primary bone tissue is formed. Osteoclasts initiate the modeling of the bone tissue.
Why is endochondral bone formation a misnomer
because endochondral means bone formation inside of cartilage and truly cartilage is replaced by bone
Where does the primary ossification center in endochondral bone formation occur
in future diaphysis of cartilage model
Explain endochondral bone formation
chondrocytes become hypertrophic, chondrocytes secrete vascular endothelial growth factors
blood vessels break through perichondrium, bringing in osteoprogenitor cells
hypertrophic cartilage cells undergo apoptosis, leaving behind thin strands of clarified matrix.
Osteoblasts use calcified strands as substrates for deposition of osteoid
Osteoid is calcified
note cartilage is ___________ by bone, it is not _________ into bone
replaced, transformed
the epiphyses and diaphyses are separated initially by _________
epiphyseal plate (growth plate)
What are the zones of the epiphyseal plate
Reserve zone, Proliferative zone, Hypertrophic zone, Vascular invasion zone
What are the functions of hypertrophic chondrocytes
Form calcified matrix, Synthesize Type X collagen, Secrete Vascular endothelial GF, Signal perichondrial cells to become osteoblasts
what is the zone of proliferation stimulated by
Indian hedgehog (ihh) which also prevents hypertrophy
What is the template of a long bone
Hyaline cartilage
what forms the periosteal collar
Osteoprogenitor cells
What is a joint
where two bones come together
What are examples of symphyses
intervertebral discs and the pubic symphysis
what are symphyses joined by
Fibrocartilage
Cartilaginous joints (amphiarthroses) are joined by
hyaline or fibrocartilage
what are the 3 types joints
Amphiarthroses, Synarthroses, Diarthroses
What are Synchondrosis joints by what
Hyaline cartilage
what are some examples of synchondroses
epiphyseal plates and the first sternocostal joint
What are the two types of cartilaginous joints (amphiarthroses)
Symphysis and Synchondrosis
What are the three types of fibrous joints (synarthroses)
Suture, Gomphosis, Syndesmosis
What are bone of Fibrous joints (synarthroses) joined by
Collagenous and/or elastic fibrous CT
Where are examples of Suture joints
between the bones of the calvaria
Where are Gomphosis joints located
This is a “peg-in- the-socket joint such as the teeth in the alveoli
Where are Syndesmosis found
bones are joined by an interosseous fibrous membrane such as the fibrous membrane between the tibia and fibula
What are synovial joints (diarthroses)
These are the movable joints exemplified by a connective capsule surrounding a fluid-filled joint space
What are synovial joints (diarthroses) reinforced by
thickenings of the outer part of the capsule referred to as ligaments
What stabilizes the capsule and the joint in synovial joints (diarthroses)
Ligaments
What is the role of ligaments in synovial joints (diarthroses)
stabilize the castle and the joint, control and restrict direction and range of motion, reinforce the synovial joints
Joints allowing movement in one plane only are _____
monaxial
What are two types of Monaxial joints
hinge joints and Pivot joints
Hinge joints include
the humeroulnar and knee joints
Pivot joints include
Atlantoaxial and radioulnar joints
Joints allowing movement in two planes are called ____
biaxial
what are two types of biaxial joints
condyloid joints and saddle (sellers) joint
Examples of Condyloid joints
metacarpophalangeal and atlantooccipital joints
Examples of saddle (sellers) joint
First carpometacarpal joint
Joints allowing movement in three planes are ____
Triaxial
What are some examples of triaxial joints
ball-and-socket joints such as the glenohumeral and the femoroacetabular joints
what are ligaments attached by
Sharpey’s fibers
Articular cartilage is composed of what kind of cartilage
Hyaline cartilage
Does the Articular cartilage lack perichondrium
Yes
Is articular cartilage lined by synovial membrane
No
What is the joint capsule composed of
Vascularized dense CT
Is the joint capsule lined by synovial membrane
Yes
The joint capsule is attached to the edges of what
the articular cartilage
The synovial membrane is composed of
highly vascularized (fenestrated capillaries)
The synovial membranes is composed of how many layers of synovial cells
1-3 layers
Does the synovial membrane have a basal lamina
No
The synovial fluid is composed of
contains mucin (hyaluronic acid- protein complex)
What produces the synovial fluid
Synovial cells
What are the two types of synovial cells
Type A and Type B
What is a type A synovial cell like
Macrophage-like
What is a Type B synovial cell like
Fibroblast-like