PSIO 201 5th Edition Exam 2 Study Guide Lectures 8 15 Lecture 13 was CANCELLED and moved to next exam Lecture 8 September 17 1 List and describe the functions of the skeletal system 2 Differentiate between the two divisions of the skeletal system and give examples 3 Describe the classification of bones based on shape giving examples for each type 4 Describe the anatomy of long bone 5 List and describe the functions of the 4 cell types found in bone 6 Discuss modeling and remodeling of bone 1 Skeletal System functions are for support protection mineral storage triglyceride storage red and white blood cell formation hemopoiesis and leverage assistance in moving 2 Axial Skeleton Skull cranium face Hyoid Auditory ossicles vertebral column and thorax sternum ribs Axial skeleton is basically the center region of the body Appendicular skeleton Pectoral Girdle clavicle scapula Upper limbs Humerus Radius Ulna Carpals Metacarpals Phalanges Pelvic Girdle Coxal Bones Pelvis and Lower Limbs Femur Tibia Fibula Patella Tarsals Metatarsals Phalanges 3 Long bones longer than they are wide Humerus phalanges Short bones cube shaped trapezoid wrist bone Flat bone plate like with broad surfaces sternum cranium rib Irregular bone varied shapes vertebra scapula osa coxa Sesamoid bone seed shaped patella Sutural bone Bones found between sutures in between cranial bones 4 Anatomy of long bone 1 Periosteum outer touch fibrous connective tissue covering continuous with tendons and ligaments Has blood vessels that penetrate the bone 2 Proximal and Distal Epiphysis broad ends of a long bone that articulate with other bones consist of spongy bone with a thin outer layer of compact bone 3 Diaphysis shaft walls consist of compact bone lined with Endosteum fine connective tissue layer 4 Medullary cavity hollow space in the diaphysis contains yellow marrow in adults 5 Articular cartilage hyaline cartilage that covers the ends of epiphyses reduced friction between bones and joints 5 Osteogenic cells important for bone growth and remodeling Osteoblast forms bone matrix and synthesis of collagen and calcification Osteocyte Mature cell maintains homeostasis senses damage in bone and sends signals for repair Osteoclast breaks down bone resorption using enzymes and acids breaks down matrix Helps regulate calcium in the blood 6 Modeling construction bone is formed by osteoblasts from scratch Remodeling reconstruction first bone is resorbed and then formed in same location by osteoblasts Goal of modeling and remodeling is to achieve peak strength and maintain bone strength by removing damaged bone Lecture 9 September 19 1 List the components of the matrix of bone and describe how each component contributes to bone strength 2 Describe the differences between compact and spongy bone in terms of location function and composition 3 Describe the microscopic structure of compact bone the osteon and understand the purpose of its organization 1 Matrix of bone Extracellular matrix is composed of Organic and Inorganic substances Organic substances secreted by osteoblasts include ground substances 1 GAGS 2 Glycoproteins polysaccharides protein 3 Negatively charged water 4 Type 1 Collagen fibrous protein arranged in helical form very resistant Microfibrils fibril fiber Inorganic substances are water attracts ground substances and Hydroxyapatite forms mineral plates Organization of Inorganic and organic components 1 Salt hydroxyapatite are deposited within collagen fibers 2 As they condense other inorganic salts precipitate to fill in spaces between collagen fibers 2 Organization of Spongy Bone irregular lattice of thin plates called trabecullae Osteocytes housed in lacunae Location of Spongy Bone surrounding marrow cavities epiphysis of long bones and flat short irregular bones Function of Spongy BoneWithstand forces from many directions trabecullae arranged along lines of stress Lightens the skeleton and contains red marrow for hemopoiesis Organization of Compact Bone solid network of bone organized in concentric ring structures called osteons Location external layer of all bones diaphysis of long bones Function gives long bones ability to withstand forces along longitude axis Lecture 10 September 22 1 Differentiate between the processes of intramembranous and endochondral ossification 2 Be able to determine the order of events involved in intramembranous and endochondral ossification 3 List the bones formed by intramembranous and endochondral ossification 4 Describe how the presence of an epiphyseal plate facilitates the lengthening of bones 5 Describe the process of appositional growth 1 Intramembranous ossification with in membrane mesenchyme to bone include cranium mandible sternum and clavicle Heterotropic bone formation sesamoid bones between feet 2 Intramembranous Ossification Steps 1 Development of ossification center Mesenchymal cells differentiate into osteogenic cells then into osteoblasts Osteoblasts secrete bone matrix 2 Calcification osteoblasts deposit calcium into the matrix osteoblasts differentiate into osteocytes 3 Development of Periosteum remodeling of spongy bone to compact bone 3 Endochondral Ossification forms most bones in body and Growth in length at the epiphyseal plate 4 Steps 1 Cartilage model forms 2 Growth of cartilage mode 3 Blood vessels penetrate model and stimulate differentiation of osteogenic cells into osteoblasts 4 Osteoblasts form bone on the outer surface of the model 5 Osteoblasts create a primary ossification center bone replaces cartilage 6 Osteoclasts create a marrow cavity 7 Spongy bone remodeled to compact bone 8 Around birth a secondary ossification center forms 9 Spongy bone replaces cartilage at the epiphyses with the exception of epiphyseal plates and articular cartilage Interstitial growth Growth from within cartilage Growth in length at epiphyseal plate Appositional growth Growth at the outer surface Growth in width 5 Epiphyseal Plate Epiphysis Resting cartilage Proliferating cartilage Hypertrophic and calcified cartilage Ossification Steps of Appositional Growth 1 Periosteal osteogenic cells differentiate into osteoblasts 2 osteoblasts build bone on outer surface of bone and endosteal osteoclasts increase the diameter of the marrow cavity 3 Bone diameter and cortical width increase Lecture 11 September 24 1 List the major components of the axial skeleton 2 List the 8 bones of the cranium and be able to describe their location and articulations with in the skull of the bone