Cartilage and Bone VIBS 443/602 OBJECTIVES GENERAL ORGANIZATION MECHANISM OF GROWTH CHARACTERISTICS OF CELLS CELLS OF CT FIBROBLASTS MESENCHYMAL CELLS and RBC ADIPOSE CELLS MACROPHAGE PLASMA CELLS MAST CELLS and WBC CHONDROBLASTS CHONDROCYTES OSTEOBLASTS OSTEOCYTES OSTEOCLASTS TYPES OF CARTILAGE HYALINE CARTILAGE ELASTIC CARTILAGE FIBROCARTILAGE 220 primary spongiosa of the Fetal finger 194 Fetal elbow 194 Fetal elbow 421 Tibia, fetal 133 Trachea, monkey Appositional growth of cartilage EM 11: cartilage 1. Chondrocyte 2. Fibroblast 3. Appositional growth region 4. Type I collagen 5. Type II collagen interstitial growth of cartilage EM 13: cartilage interstitial growth of chondrocytes 1. 2 daughter chondrocytes resulting from interstitial growth 2. Rough endoplasmic reticulum HYALINE CARTILAGE EPIPHYSEAL PLATE, RESPONSIBLE FOR LONGITUDINAL GROWTH OF LONG BONES 220 cartilage growth in endochondral bone formation of the Fetal finger OSTEOBLAST OSTEOCLAST OSTEOCLAST OSTEOBLAST Elastic cartilage in pina of ear #19762 Connective tissue epithelium Connective tissue epithelium Elastic cartilage Elastic cartilage FIBROCARTILAGE INTERMEDIATE BETWEEN DENSE REGULAR CONNECTIVE TISSUE AND HYALINE CARTILAGE NO PERICHONDRIUM 194 Fibrocartilage of Fetal elbow Fibrocartilage Fibrocartilage 194 Fibrocartilage of Fetal elbow Fibrocartilage 194 Fibrocartilage of Fetal elbow Fibrocartilage 220 Fetal finger – fibroblasts in tendon Tendon Fibrocartilage endochondral bone formation CELLS OF BONE OSTEOBLASTS - SECRETE OSTEOID - BONE – EXPAND BONE BY APPOSITIONAL GROWTH OSTEOCYTE = OSTEOBLAST TRAPPED IN MATRIX OF BONE APPOSITIONAL GROWTH EM 12: osteoblast adjacent to osteoid; bone; RER and Golgi 1. Rough endoplasmic reticulum 2. Golgi 3. Osteoid 4. Nucleus of osteoblast CELLS OF BONE FUNCTIONS OF BONE CALCIUM REGULATION Parathroid hormone (BONE RESORPTION) Calcitonin (PREVENTS RESORPTION) These HORMONES are INVOLVED IN TIGHT REGULATION as 1/4 OF FREE CA++ IN BLOOD IS EXCHANGED EACH MINUTE. HEMOPOIESIS COMPACT BONE HAVERSIAN SYSTEMS LAMELLAE OF BONE AROUND HAVERSIAN CANAL LINKED BY VOLKMANN’S CANAL COMPACT BONE REMODELING Over time COMPACT BONE REMODELING Slide 121: compact bone (unstained ground bone) 1. Blood vessel 2. Haversian canal 3. Interstitial system 4. Lacuna 425 Bone (unstained) 425 Bone (unstained) 121 Bone, rabbit femur 121 Bone, rabbit femur 121 Bone, rabbit femur 421 Tibia, fetal 195 Osteoblasts in the Fetal jaw 195 Osteoclasts, osteoblasts, and osteocytes in Fetal jaw osteoclasts osteocytes osteoblasts 420 Rib 220 How many Osteoclasts of Fetal finger can you spot? Osteoclasts ENDOCHONDRAL (SPONGY/ CANCELLOUS) BONE FORMATION CARTILAGE MODEL CENTERS OF OSSIFICATION PRIMARY CENTER OF OSSIFICATION • DIAPHYSIS SECOND CENTER OF OSSIFICATION • CENTER OF EACH EPIPHYSIS 220 cartilage growth in endochondral bone formation of the Fetal finger 194 Articular surfaces of hyaline cartilage of the Fetal elbow HISTOGENESIS OF BONE INTRAMEMBRANOUS OSSIFICATION FLAT BONES OF SKULL SKELETAL CONNECTIVE TISSUE 420 420 420 420 420 32583 32583 32583 32583 32583 32583 32583 Polychromatic normoblast 32583 32583