Bones and Bone Tissue - These are definitions for the basic terminology in biology. PDF

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These are definitions for the basic terminology in biology....

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appositional growth: bone growth in width bone collar: The osteoblasts produce compact bone on the surface of the cartilage model. Bone growth in length occurs at the epiphyseal plate in __________.: long bones Bone is the most important storehouse in the body for __________.: calcium bone remodeling continues after growth: Involves a cycle of bone formation (deposition) and bone breakdown (resorption), During growth deposition exceeds resorption, In healthy bone of adults deposition and absorption are balanced Bones are constantly undergoing resorption for various reasons. Which of the following cells accomplishes this process?: osteoclasts Bones with a diaphysis and epiphyses are classified as __________.: long bones Canaliculi: Hairlike canals that connect lacunae to each other and the central canal central canal: center of each osteon where blood vessels and nerves are located, osteocytes residing in lacunae obtain nutrients from blood supply Charlie has a break in the shaft of his thigh bone. He broke the __________.: diaphysis compact bone: Hard, dense bone tissue that is beneath the outer membrane of a bone compound fracture: bone breaks through the skin compression: Squeezing or pressing together, Bones are pressed between body's weight and ground stimulates bone deposition Correctly order the following key steps in the process of endochondral ossification. 1. Chondrocytes die. 2. Osteoblasts build the bone collar on the external surface of the bone. 3. Perichondrium is invaded by blood vessels. 4. In the primary ossification center, osteoblasts replace calcified cartilage with early spongy

bone. 5. Perichondrial cells differentiate into osteogenic cells then into osteoblasts.: 3, 5, 2, 1, 4 Diaphysis: shaft of a long bone endochondral ossification: occurs from within a model of hyaline cartilage, cartilage serves as a scaffold for developing bone, all bones below head except clavicles, also begins in fetal stage, many bones complete ossification by age 7 Endosteum: membranous lining of the hollow cavity of the bone enzymes: break down organic matrix epiphyseal line: remnant of the epiphyseal plate, seen in adult bones epiphyseal plate (growth plate): area of hyaline cartilage that separates the marrow spaces of the epiphysis and diaphysis Epiphysis: the end part of a long bone, initially growing separately from the shaft. factors that influence bone remodling: age, calcium ion intake from diet, vitamin d intake from diet, vitamin c intake from diet, vitamin k intake from diet, protein intake from diet flat bones: These bones are thin, flat, and curved. They form the ribs, breastbone, and skull. Fontanels: Gaps between a baby's skull that slowly close up during the first 18 months of life; "soft spots" For a person who starts running for exercise, __________.: bone deposition exceeds bone resorption Fracture healing process: hematoma formation, fibrocartilage callus formation, bony callus formation, bone remodeling function of skeletal system: support, protection, movement, storage, blood cell production Glycoproteins: bind all of different components of both matrixes together

glycosaminoglycans and proteoglycans: create osmotic gradient that draws water into matrix, helps tissue resist compression Hematopoiesis: blood cell formation How long does bone repair generally take?: 6-8 weeks hydrogen ions: dissolve components of inorganic matrix inorganic matrix: minerals, mainly calcium, also sodium, phosphorus and magnesium interstitial lamellae: remains of old osteons that broke down as bone grew and remodeled itself intramembranous ossification: bone develops from a fibrous membrane; forms many flat bones including bones of skull and clavicles, during fetal development irregular bones: bones of the vertebrae and face lacunae: cavity in matrix lamellae: rings of thin layers of bone, very stress resistant, collagen fibers of neighboring lamellae run in opposite directions, resist twisting and bending forces long bones: longer than they are wide; bones of the arms and legs, Humerus, Radius, Ulna, Femur, Fibula and Tibia longitudinal growth: bone growth in length medullary cavity: cavity within the shaft of the long bones filled with bone marrow; forms and enlarges as calcified cartilage is removed movement: skeletal muscles attach to bones, muscle contraction pulls on bones and generates force for movement at a joint organic matrix: collagen fibers and other components Ossification (osteogenesis): process of bone formation; continues until age 7 osteoblasts: bone forming cells

osteoclasts: Bone-destroying cells osteocytes: mature bone cells; osteoblasts that surround themselves with bone matrix in a small cavity, no longer actively synthesizing bone matrix, build up or reinforce bone under tension Osteon (Haversian system): A unit of bone containing central canal and matrix rings perforating canals (Volkmann's canals): Connect the haversian canals with each other and the periosteum.

Small channels in bone that transmit blood vessels from the periosteum into the bone and that communicate with the Haversian canals. The perforating canals provide energy and nourishing elements for osteons. perforating fibers (Sharpey's fibers): thick bundles of collagen that extend from the periosteum into the bone extracellular matrix periosteum: A dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles. pressure: Continuous downward force, Stimulates bone resorption in stimulated primary ossification center: a region where bone tissue will replace most of the cartilage Primary ossification centers develop in long bones in the __________.: diaphysis red bone marrow: found in cancellous bone; site of hematopoiesis Role of Hormones in Bone Growth (Anterior pituitary gland secretes growth hormone): 2. anterior pituitary gland secretes growth hormone that enhances protein synthesis and cell division through the body, increases rate of cell division of chondrocytes in epiphyseal plate, increases ossification, directly stimulates osteoblasts in appositional growth

Role of Hormones in Bone Growth (Female sex hormone estrogen affects bone growth): 4. Increase rate of longitude bone growth, Inhibits osteoclast activity, When estrogen levels spike in teen years an accompanying "growth spurts" occurs in female, Accelerates closure of epiphyseal plate at a much faster rate than testosterone, Leads to average Height difference between genders Role of Hormones in Bone Growth (Hormones are one of the main factors affecting bone growth): 1. secreted by cells of endocrine glands Role of Hormones in Bone Growth (Testosterone affects bone growth): 3. testosterone increases appositional growth in males, and more calcium salt deposition than in female, Increase rate of mitosis in epiphyseal plate "growth spurts" in teenage years, Accelerates closure of epiphyseal plate sesamoid bones: small, flat, oval-shaped; round bones found near joints (e.g., the patella) short bones: as long as they are wide; bones of the wrist and ankles short, flat, irregular, and sesamoid bones: They do not have diaphysis, epiphysis, medullary cavities, epiphyseal lines, or epiphyseal plates simple fractures: skin and tissue around fracture remain intact Sinuses: air filled spaces which reduce bone weight, in some flat and irregular bones of skull skeletal system components: Bones and joints of the body and their associated cartilages. spongy bone: Layer of bone tissue having many small spaces and found just inside the layer of compact bone. support: provides structural framework and supports weight of body tension: Stretching force, Stimulates bone deposition

The function of yellow bone marrow is __________.: triglyceride storage The structural units of mature compact bone are called __________.: osteons three types of bone cells: osteoblasts, osteocytes, osteoclasts trabeculae: struts or ribs of bone, covered with endosteum, provide strength and resist forces from multiple directions, protects bone marrow that has rich blood supply from which it gets its nutrients, usually not arranged into osteons, composed of concentric lamellae, lacunae containing osteocytes, canaliculi two major types of bones: dense and spongy Which hormone, produced by the thyroid gland, works opposite to parathyroid hormone (PTH)?: calcitonin Which of the following promotes bone resorption?: pressure Whose bone marrow is mostly red?: infants Within the epiphyseal plate, which zone houses actively dividing cartilage cells in their lacunae?: zone of proliferation yellow bone marrow: stores fat; used for energy zone of proliferation: dividing chondrocytes, elongation of cartilage, calcification follows replaced with spongy bone and then dense bone, bone growth takes place on side closest to diaphysis...