Chapter 6: Skeletal System: and Tissue

I. Functions A. List and describe the five major functions of the skeletal system: 1. ______2. ______3. .______4. ______5. .______

II. A. What do do? ______B. When a becomes surrounded by matrix it is called ______C. 1. The outer layer is composed of ______2. The inner layer has ______3. Blood vessels penetrate ______D. Where is articular cartilage found? ______E. Describe appositional growth: ______F. Describe interstitial growth: ______

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III. Bone Histology A. Bone Matrix 1. Composed of 35% ______& 65% ______2. Hydroxyapatite is ______3. Functionally collagen fibers in bone ______4. Functionally the mineral matrix in bone ______B. Bone Cells 1. a. These cells produce ______& ______b. In addition to various enzymes osteoblasts also form vesicles that accumulate ______& ______c. All vesicles are released by ______d. Define : ______2. a. When does an become an ? ______b. Osteocytes produce components needed to ______c. Osteocytes sit in a space called a ______d. The spaces that contain osteocyte cell processes are called ______e. Nutrients and gases pass through ______3. a. Describe an ______b. Osteoclasts are responsible for ______4. Origin of Bone Cells a. Osteoblasts are derived from ______b. Osteocytes are derived from ______c. Osteoclasts are derived from ______C. Woven and Lamellar Bone 1. In woven bone collagen fibers are ______2. When is woven bone formed? ______& ______3. Explain remodeling: ______

Page 2 of 10 4. Lamellar bone is organized into ______called ______5. In lamellar bone the collagen fibers ______6. How are osteocytes arranged in lamellar bone? ______D. Cancellous and Compact Bone 1. Cancellous bone has ______& ______2. Compact bone has ______& ______3. Cancellous Bone a. lt consists of ______called ______b. The spaces are filled with ______& ______c. Trabeculae are oriented ______4. Compact Bone a. The Iamellae are oriented around ______b. Blood vessels that run parallel to the bone’s long axis are contained within ______or ______c. The concentric lamellae ______d. An (haversian system) consists of ______1. If cut in cross section it resembles ______e. Describe the three types of lamellae: 1. Concentric ______2. Circumferential ______3. Interstitial ______f. How do perforating (Volkmann’s) canals differ from central (haversian) canals? ______

IV. Bone Anatomy A. Describe each of the four basic bone shapes: 1. ______2. ______3. ______4. Irregular bone ______B. Structure of a Long Bone

Page 3 of 10 1. The is composed primarily of ______2. Where is the diaphysis? ______3. What is an ? ______4. The epiphysis is composed primarily of ______that is covered by a layer of ______& at joints ______5. What is the composed of? ______6. Where is the epiphyseal plate located? ______7. What occurs at the epiphyseal plate? ______8. When the epiphyseal plate is ossified it is called ______9. Inside the diaphysis is a large space called ______10. Red marrow is the site of ______while yellow marrow is ______11. The outer surface of the bone is covered by the ______a. The outer layer is composed of ______b. The inner layer is composed of ______12. How are tendons and ligaments attached to the bone? ______13. The inside of the is lined by the ______a. This membrane is composed of: ______C. Structure of Flat, Short, and Irregular Bones 1. Flat bones have an interior ______of ______that is sandwiched between ______2. Short and irregular bones have a surface layer of ______that surrounds ______3. Air filled spaces inside flat and irregular bones are called ______a. These spaces are lined by ______

V. Bone Development A. Intramembranous Ossification 1. Begins when mesenchymal cells in the membrane become______2. These cells specialize to become ______

Page 4 of 10 3. The osteoblasts produce ______that surrounds ______a. This is a “center of ossification”. 4. This process forms many tiny ______of ______5. The trabeculae enlarge as ______6. As the trabeculae join together they form ______separated by ______7. Cells within the spaces specialize to form ______8. Cells surrounding the developing bone specialize & form ______9. An outer surface of compact bone is formed by ______10. The end product of intramembranous ossification: a. Bones with outer ______& b. ______centers 11. Remodeling forms ______bone and ______B. Endochondral Ossification 1. Begins as ______aggregate ______2. The cells become ______& produce a ______having the approximate shape of the future bone 3. When surrounded by matrix the chondroblasts become ______4. The cartilage model is surrounded by ______5. Blood vessels penetrating the perichondrium cause ______to become ______6. When bone is being produced the perichondrium becomes______7. The osteoblasts produce ______on the surface of the cartilage model forming a ______8. The cartilage continues to grow by ______& ______9. inside the cartilage model ______10. The matrix between becomes ______with ______is referred to as ______11. The chondrocytes then ______leaving ______

Page 5 of 10 12. What grows into the enlarged lacunae? ______13. This results in osteoblasts forming ______, which changes the calcified matrix of the diaphysis into ______a. The area of bone formation in the diaphysis is called______14. As ossification proceeds: a. The cartilage model ______b. More perichondrium ______c. The bone collar ______d. Within the diaphysis ______15. Remodeling converts ______bone to ______bone and ______16. Osteoclasts ______17. Cells within the medullary cavity ______18. Secondary ossification centers appear ______a. What happens differently at secondary ossification centers compared to primary ossification centers? ______19. Eventually all cartilage in the model is replaced by bone except: a. In the ______b. And on ______VI. Bone Growth A. Occurs only by ______growth B. Growth in Bone Length 1. Growth at the epiphyseal plate involves ______of new ______by ______growth followed by ______bone growth. 2. Describe the events in each of the four zones of the epiphyseal plate: a. Zone of resting cartilage ______b. Zone of proliferation ______

Page 6 of 10 ______c. Zone of hypertrophy ______d. Zone of calcification ______3. What part of the bone is increasing in length? ______4. The thickness of the epiphyseal plate stays the same because: a. Rate of ______on the ______side is b. Equal to ______on the ______side 5. When the epiphyseal plate stops growing and is ossified it is ______C. Growth at Articular Cartilage 1. Growth at the articular cartilage increases size of ______2. How does this process differ from what occurs at the epiphyseal plate? ______3. How long does the articular cartilage remain on the epiphyses? ______D. Growth in Bone Width 1. Bones increase in width due to ______under _____ 2. When growth in width is rapid: a. Osteoblasts lay down bone in ______with ______between them b. covers the ridges and grooves and one or more ______of the periosteum lie ______c. The ridges increase in size eventually forming ______d. Since the periosteum of the tunnel is now lining bone it is a ______e. Concentric lamellae are formed by ______of the ______f. Eventually this fills in the tunnel and forms an ______3. When growth in width is slow: a. Circumferential lamellae are formed making the bone surface _____ b. Remodeling breaks down the ______& forms ______

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E. Factors Affecting Bone Growth I Nutrition 1. Nutrition a. What role does Vitamin D play in bone growth? ______b. What role does Vitamin C play in bone growth? ______2. Hormones a. Growth hormone stimulates: 1. ______& 2. ______b. Thyroid hormone is required for ______c. Estrogen and testosterone: 1. Initially ______2. Also stimulate ossification of ______d. Why are females usually shorter than males? ______

VII. Bone Remodeling A. Bone remodeling: 1. Converts ______bone to ______bone 2. Is involved in ______3. Changes in ______4. Adjustment of bone to ______5. Bone ______6. ______in the body B. Remodeling causes the diameter of the medullary cavity to ______as the bone increases in length and width. 1. What is the advantage to having a medullary cavity? ______C. Remodeling is also involved in the formation of ______in bone. D. What do interstitial lamellae represent? ______

Page 8 of 10 VIII. Bone Repair A. Hematoma Formation 1. A hematoma is ______a. The blood usually forms a ______that ______2. What happens to the bone tissue adjacent to the fracture site?______B. Callus Formation 1. A callus is ______a. Internal callus 1. Forms between ______& in the ______2. As the clot dissolves: a. Macrophages ______b. Osteoclasts ______c. Fibroblasts produce ______3. A denser fibrous network is formed when ______a. This helps to ______4. Chondroblasts begin to ______5. Osteoblasts produce ______that ______b. External Callus 1. Forms a ______2. Osteoblasts produce ______& chondroblasts produce ______a. Therefore the external callus is a ______collar 3. The external callus ______the ______of the broken bone C. Callus Ossification 1. The cartilage in the external callus is replaced by ______through ______a. This results in a ______external callus 2. When is the internal callus ossified? ______D. Remodeling of Bone 1. Repair is not complete until ______and ______

Page 9 of 10 IX. Calcium Homeostasis A. Blood calcium levels are important for normal function of ______& ______B. When blood calcium levels are too low ______C. When blood calcium levels are too high ______D. Parathyroid hormone secretion increases when ______E. Functionally parathyroid hormone: 1. Increases the numbers of ______2. Causes osteoblasts to ______3. Increases calcium uptake by ______4. Increases calcium reabsorption ______F. Calcitonin is secreted by the ______G. Calcitonin is secreted in response to ______H. Functionally calcitonin ______

X. Effects of Aging on the Skeletal System A. The most significant changes affect the ______& ______of matrix B. What does decreased collagen production do to bone matrix? ______C. Osteoblasts become slower than osteoclasts resulting in ______D. Cancellous bone is lost ______as the trabeculae ______& ______E. What happens when trabeculae become disconnected from each other? ______F. Most loss of compact bone occurs ______G. Incomplete bone remodeling causes ______H. Loss of trabeculae greatly increases the chance of ______I. Loss of bone can cause: 1. ______2. Loss of ______3. ______& 4. ______

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