Worksheet – Bone Tissue

WORKSHEET – BONE TISSUE – BIOLOGY List 5 functions of bone 1. Supporting & protecting soft tissues 2. attachment site for muscle making movement possible 3. storage of the minerals, calcium & phosphate minerals homeostasis 4. blood cell production (hemopoiesis) occurs in red bone marrow 5. triglyceride storage in yellow bone marrow List the 5 classes of bone based on shape. Include examples of each. 1. long bone 2. short bone 3. flat bone 4. irregular bone 5. Seamoid bone The shaft of a long bone is the Diaphysis The end of a long bone is the Epiphysis What is the function and type of articular cartilage? Hyaline What is found in the medullary (marrow) cavity of a long bone? yellow bone marrow. Periosteum. is the connective tissue covering of bone and endosetum. lines the medullary cavity. How does the structure of short, flat, irregular, and sesamoid bones differ from long bones? they do not have diaphyses, epiphyses, medullary cavities. or epiphyseal plates Where is red bone marrow found in an adult, and what is its function? 1 | Page red bone marrow is found in only in pelvis, proximal femur and humerus, vertebrae, ribs, sternum, clavicales, scapulae, and some bones of skull. Its function is to loose connective tissue and support islands of blodd forming hemtaopoietic cells. Hydroxyapatite is an inorganic mineral salt that provides bone’s hardness. Organic collagen fibers. provides bone’s flexibility. List the 4 cell types in bone 1. Osteogenic cells 2. Osteoblasts 3. Osteocytes 4. Osteoclasts. Which cell type forms the matrix and thus functions in bone deposition? Osteoblasts . Which cell type releases enzymes that breaks down bone matrix and thus functions in bone resorption? Osteoclasts Osteocytes. are mature bone cells that are surrounded by matrix in a small cavity called a lacunae What cell type can divide and then become an osteoblast? Osteogenic cells. Compact and Spongy Bone Where is spongy bone found? found in ends of long bones and inside flat bones such as the hipbones, sternum, sides of the skull, and ribs. Where do you find compact bone? makes up the shaft of long bones and the external all layers of all bones. The structural unit of compact bone is the osteon (Haversian System). List the 3 canals associated with the osteon 2 | Page 1. Peforating canals. 2. Central canals. 3. Canaliculi. The thin circular layers of bone surrounding the central canals is referred to as Concentric lamellae The struts of bone oriented along lines of in spongy bone are called Trabculae Ossification and Bone Growth Define the following 2 types of ossification Intramembranous bone formation – are built on a model (strating material) made of the membrane of embryonic connective tissue. Endochondral ossification – are built on model of hyaline cartilage Bone growth in length involves the production of cartilage cells on the Click or tap here to enter text.side of the plate and bone deposition on the Click or tap here to enter text.side of the plate. List the 5 zones of the epiphyseal growth plate with a description of what is happening at each. (Epiphyseal side to diaphyseal side of plate) 1. Zone of resting (reserve) cartilage - anchors growth plate to bone 2. Zone of proliferating cartilage - rapid cell division of chondrocytes (stacked coins) 3. Zone of the hypertrophic cartilage - cells enlarged and remaining in column: mature chondrocytes 4. Zone of calcified cartilage - thin zone, cells mostly since matrix has calcified 5. Zone of ossification - osteoclasts remove calcified cartilage, osteoblasts and capillaries move in to create bone over calcified cartilage, and unilmately calcified cartilage and primary bone are restored by osteoclasts and completely replaced with mature bone 3 | Page Between the ages of 12-15 years. the zone of proliferation is completely ossified. Bone growth and width is called Appositional growth Hormones Involved in Bone Growth Identify the effect of each of the following hormones on bone growth Growth hormone - increases rate of cell division of chondrocytes in epiphyseal plate - increases activity of osteogenic cells, including activity in zone of ossification - directly stimulates osteoblasts in periosteum; triggers appostional growth Testosterone - increases appostioinal growth; bones in males become thicker with more calcium salt deposition than females - increase rate of mitosis in epiphyseal plate leads to growth spurt in teenage years - accelerates closure of epiphyseal plate - increases rate of longitudinal bone growth; inhibits osteoclast activity - when estrogen levels spike in teen years, an accompanying “growth Estrogen spurt” occurs in females - Accelerates closure of epiphyseal plate at much faster rate than testosteron; leads to acreage height difference between genders List 5 reasons that Bone Remodeling occurs 1. maintenance of calcium ion homeostasis 2. Replacement of primary bone with secondary bone. 3. bone repair. 4. Replacement of old brittle bone with newer bone 4 | Page 5. Adaptation to tension and stress During bone remodeling, osteoclasts function in bone resorption. which is the removal of minerals and collagen to the bone. During bone remodeling, osteoblasts function in bone osteoblasts. which is the addition of minerals and collagen to the bone. Bone Fractures Identify the following bone fractures There is a break in the skin Open fracture (compound) Happens only in children due to the higher concentration of collagen fibers Greenstick No break in the skin Closed (simple) Microscopic fissures from repeated strenuous activities stress fracture List the 4 phases of fracture repair 1. formation of fracture hematoma. 2. formation of fibrocartilagenous Callus 3. Formation of bony callus 4. Bone remodleling What type of cartilage is used deposited during soft callus formation? Fibrocartilagenous Mineral Homeostasis What hormone is secreted when blood calcium levels are low? parathyroid The above hormone has what effect on blood calcium levels? Parathyroid What effect would the above hormone have on bone mass? bone mass would increase. where bone deposition pulls calcium ions out of the blood to manufacture 5 | Page an inorganic bone matrix that is most active during bone growth and less so in adulthood. What hormone is secreted when blood calcium levels get too high? Parathyroid glands cells What effect would the above hormone have on osteoclastic activity, and what effect would it have on blood calcium levels? PTH stimulates effects that increase blood calcium ion levels. The increased osteoclast activity breaks down the inorganic maxtrix of bone, releasing calcium ions from hydroyapatite crystals. What condition results in decrease in bone mass? porous bones Explain why menopause can result in osteoporosis because of it low level of ostrogen increase the risk developing osteoporosis Low vitamin D levels results in Rickets in children and osteomalacia in adults. Osteomyelitis.is an infection of the bone. What bone cancer primarily affects the osteoblasts in teenagers? Osteosarcoma 6 | Page