Connective Tissue Growth

Flashcards about Connective Tissue Growth

What is Chondrogenesis?

Cartilage formation

What is a Chondroblast?

Immature, bone anlage cell

What is a Chondrocyte?

Mature, ECM-producing cartilage cell

What is Osteogenesis?

Bone formation

What is 'Anlage'?

Embryological groupings of stem cells that will form a future structure or organ

What is Endochondral ossification?

Bone formation that relies on cartilaginous anlage

What is Intramembranous ossification?

Bone formation that does not rely on cartilaginous anlage

What is Osteoblast?

Immature, post-mitotic, osteoid producing bone cell

What is Osteocyte?

Fully-differentiated osteoblast; mature, fixed, bone cell – maintain mineral balance of bone

What are Osteoclasts?

Post-mitotic bone destroying cells

What is Osteoid?

Unmineralized ECM capable of binding Ca2+

What does the appendicular skeleton include?

Bones associated with appendages - Long bones of limbs, bones of fore- & hind-limbs, pelvic & shoulder girdle

What does the axial skeleton include?

Everything that is not part of appendicular - Skull, vertebrae, thoracic bones of the ribcage

Name 3 main categories of Connective Tissue

Proper, Supportive, and Specialized

What are the components of Connective Tissue?

Cells, Protein fibers, Ground substance, Extracellular Matrix (ECM)

What are some examples of connective tissue protein fibers?

Collagen, Reticular, Elastic

What is Fibrillar collagen?

Most abundant protein found in animals (23‐30% of total protein)

What does Collagen III provide?

Support within organs, glands, etc., and/or fine structural support

What is special about Elastin?

Can be reversibly stretched to twice original length

Connective tissue proper contains what?

Fibroblasts

Supportive connective tissue contains what?

Cartilage = Chondrocytes, Bone = Osteocytes

Specialized tissue contains what?

Adipose = Fibroblasts + Adipocytes, Blood & Lymph = Erythrocytes, Lymphocytes, Platelets

What are function of chondrocytes?

Create cartilaginous anlage and Present in adults for structures that require mechanical support

What is the function of pre-chondrocytes?

Mature chondrocytes and Begin to produce components for ECM

What effect does hypertrophy + increasing ECM volume have?

Anlage Elongation

What is the Diaphysis?

Shaft of long bone

What is the Epiphyses?

Ends of long bone

What is the Medullary cavity?

Hollowed out part of diaphysis

What is the Endosteum?

Thin connective tissue lining of medullary cavity

What is the Periosteum?

Fibrous connective tissue covering outer surface of bone - Plays critical role in bone-formation

What is the Metaphysis?

Region of bone between epiphyses & diaphysis - Important for bone lengthening

What is Spongy bone?

Thin, porous bone tissue - Interior/ends of some bones (ex., epiphyses of long bones); network for bone marrow

What is Compact bone?

Thick, dense bone tissue - Bone tissue that can support tendon & ligament attachment

What are ossification centers?

Sites within cartilaginous anlage where cartilage is replaced by bone

1o ossification center (POC) is?

Site in diaphysis

2o ossification centers (SOC) is?

Sites in epiphyses

What is the Perichondrium?

Connective tissue layers around anlage

What is function of Bone collar?

Calcifying region of periosteum encircling diaphysis

Cartilage canals are what?

Tubes that penetrate embryonic epiphyseal cartilage Enable blood vessel precursors and eventually blood vessels to penetrate cartilage of epiphyses

What does simultaneous endochondral & intramembranous ossification cause?

Long bone growth

Increase in length through what?

Growth plate

What is appositional growth?

Increase in diameter through modeling

What are Growth plate layers/zones?

Resting zone, Proliferative zone, Hypertrophic zone, Calcification/Apoptotic zone, Ossification zone, Metaphysis

What is a function of osteoclast?

Resorb ECM, especially bone

What is a function of osteoblast?

Immature, post-mitotic, osteoid creating cell

What is the role of osteocytes?

Maintain mineral balance of bone

Lengthening continues while what?

growth plate chondrocyte proliferation outpaces bone formation

What is Epiphyseal closure?

growth plate ossifies - Fuses epiphyses to diaphysis

What happens in the medullary cavity?

Osteoclasts in POC activated and Resorb woven spongy bone from center‐outwards

Describe Bone remodeling:

Occurs throughout life and Adapt to changing circumstances

What are Articular cartilage main components?

Chondrocytes, collagen, and water

What is the role of chondrocytes within zone 1?

Enable cartilage to grow laterally

What is the role of chondrocytes within zone 3?

Enable cartilage to get thicker