Transcript Spongy bone
PowerPoint® Lecture Slides prepared by Janice Meeking, Mount Royal College CHAPTER 6 Bones and Skeletal Tissues Copyright © 2010 Pearson Education, Inc. Cartilage in external ear Cartilage in Intervertebral disc Cartilages in nose Articular Cartilage of a joint Epiglottis Thyroid cartilage Cricoid cartilage Larynx Trachea Lung Costal cartilage Respiratory tube cartilages in neck and thorax Pubic symphysis Meniscus (padlike cartilage in knee joint) Articular cartilage of a joint Bones of skeleton Axial skeleton Appendicular skeleton Cartilages Hyaline cartilages Elastic cartilages Fibrocartilages Copyright © 2010 Pearson Education, Inc. Figure 6.1 Copyright © 2010 Pearson Education, Inc. Figure 6.2 Articular cartilage Proximal epiphysis Compact bone Spongy bone Epiphyseal line Periosteum Compact bone Medullary cavity (lined by endosteum) (b) Diaphysis Distal epiphysis (a) Copyright © 2010 Pearson Education, Inc. Figure 6.3a-b Endosteum Yellow bone marrow Compact bone Periosteum Perforating (Sharpey’s) fibers Nutrient arteries (c) Copyright © 2010 Pearson Education, Inc. Figure 6.3c Spongy bone (diploë) Compact bone Trabeculae Copyright © 2010 Pearson Education, Inc. Figure 6.5 Structures in the central canal Artery with capillaries Vein Nerve fiber Lamellae Collagen fibers run in different directions Twisting force Copyright © 2010 Pearson Education, Inc. Figure 6.6 Nerve Vein Artery Canaliculus Osteocyte in a lacuna Lamellae Central canal Lacunae (b) Copyright © 2010 Pearson Education, Inc. Figure 6.3b Spongy bone Compact bone Central (Haversian) canal Perforating (Volkmann’s) canal Endosteum lining bony canals and covering trabeculae Osteon (Haversian system) Circumferential lamellae (a) Perforating (Sharpey’s) fibers Lamellae Nerve Vein Artery Canaliculi Osteocyte in a lacuna (b) Copyright © 2010 Pearson Education, Inc. Periosteal blood vessel Periosteum Lamellae Central canal Lacunae Lacuna (with osteocyte) (c) Interstitial lamellae Figure 6.7a-c Bone Development Copyright © 2010 Pearson Education, Inc. Month 3 Week 9 Birth Childhood to adolescence Articular cartilage Secondary ossification center Epiphyseal blood vessel Area of deteriorating cartilage matrix Hyaline cartilage Spongy bone formation Bone collar Primary ossification center 1 Bone collar Epiphyseal plate cartilage Medullary cavity Blood vessel of periosteal bud 2 Cartilage in the 3 The periosteal forms around center of the hyaline cartilage diaphysis calcifies model. and then develops cavities. bud inavades the internal cavities and spongy bone begins to form. Copyright © 2010 Pearson Education, Inc. Spongy bone 4 The diaphysis elongates and a medullary cavity forms as ossification continues. Secondary ossification centers appear in the epiphyses in preparation for stage 5. 5 The epiphyses ossify. When completed, hyaline cartilage remains only in the epiphyseal plates and articular cartilages. Figure 6.9 Week 9 Hyaline cartilage Bone collar Primary ossification center 1 Bone collar forms around hyaline cartilage model. Copyright © 2010 Pearson Education, Inc. Figure 6.9, step 1 Area of deteriorating cartilage matrix 2 Cartilage in the center of the diaphysis calcifies and then develops cavities. Copyright © 2010 Pearson Education, Inc. Figure 6.9, step 2 Month 3 Spongy bone formation Blood vessel of periosteal bud 3 The periosteal bud inavades the internal cavities and spongy bone begins to form. Copyright © 2010 Pearson Education, Inc. Figure 6.9, step 3 Birth Epiphyseal blood vessel Secondary ossification center Medullary cavity 4 The diaphysis elongates and a medullary cavity forms as ossification continues. Secondary ossification centers appear in the epiphyses in preparation for stage 5. Copyright © 2010 Pearson Education, Inc. Figure 6.9, step 4 Childhood to adolescence Articular cartilage Spongy bone Epiphyseal plate cartilage 5 The epiphyses ossify. When completed, hyaline cartilage remains only in the epiphyseal plates and articular cartilages. Copyright © 2010 Pearson Education, Inc. Figure 6.9, step 5 Month 3 Week 9 Birth Childhood to adolescence Articular cartilage Secondary ossification center Epiphyseal blood vessel Area of deteriorating cartilage matrix Hyaline cartilage Spongy bone formation Bone collar Primary ossification center 1 Bone collar Epiphyseal plate cartilage Medullary cavity Blood vessel of periosteal bud 2 Cartilage in the 3 The periosteal forms around center of the hyaline cartilage diaphysis calcifies model. and then develops cavities. bud inavades the internal cavities and spongy bone begins to form. Copyright © 2010 Pearson Education, Inc. Spongy bone 4 The diaphysis elongates and a medullary cavity forms as ossification continues. Secondary ossification centers appear in the epiphyses in preparation for stage 5. 5 The epiphyses ossify. When completed, hyaline cartilage remains only in the epiphyseal plates and articular cartilages. Figure 6.9 Bone growth Cartilage grows here. Bone remodeling Articular cartilage Epiphyseal plate Cartilage is replaced by bone here. Cartilage grows here. Cartilage is replaced by bone here. Copyright © 2010 Pearson Education, Inc. Bone is resorbed here. Bone is added by appositional growth here. Bone is resorbed here. Figure 6.11 Factors in Bone Health Factor Effect Parathyroid hormone Stimulates osteoclasts, causes bone resorption, increases blood calcium Calcitonin Inhibits osteoclasts, builds bone, decreases blood calcium Vitamin D Promotes calcium and phosphorous absorption in gut, decreases urinary loss of calcium Sex hormones – testosterone, estrogens Stimulate osteoblasts Growth hormone Builds bone Diet - protein, calcium, Provides building blocks for phosphorous, vitamins A, C, D, bone, and helps metabolism Weightbearing exercise Copyright © 2010 Pearson Education, Inc. Stresses bone, stimulate osteoblasts Calcium homeostasis of blood: 9–11 mg/100 ml BALANCE BALANCE Stimulus Falling blood Ca2+ levels Thyroid gland Osteoclasts degrade bone matrix and release Ca2+ into blood. Copyright © 2010 Pearson Education, Inc. Parathyroid glands PTH Parathyroid glands release parathyroid hormone (PTH). Figure 6.12 Copyright © 2010 Pearson Education, Inc. Figure 6.16 Age-Related Changes in Trabecular Bone Copyright © 2010 Pearson Education, Inc. 22 M. Ding et al. Kyphosis www.hhs.gov/od/images/ NLS0601Zhangfig1.JPG Copyright © 2010 Pearson Education, Inc. 23 Copyright © 2010 Pearson Education, Inc. 24 Which two hormones work in opposition to control homeostatic blood levels of calcium via bone remodeling? • Thyroid hormone and estrogen • Parathyroid hormone and calcitonin • Calcitonin and estrogen • Parathyroid hormone and estrogen Copyright © 2010 Pearson Education, Inc.