Exam #3 Flashcards

Question

Osteoblast cells

Answer 1

Bone forming cells Dividing cells on bone surfaces Secrete organic components of matrix Help mineralize the bone matrix calcification

Answer 2

Bone destroying cells Break down bone Parathyroid hormone increases their activity

Answer 3

Osteon Structural unit Run parallel to bones long axis Lamellae layers Central canal blood vessels nerve fibers Perforating canals volkmann's canals Canaliculi osteocytes in lacunae

Answer 4

No osteons Network of trabeculae thin bony plates contain lamellae osteocytes in lacunae and canaliculi Align along lines of stress

Answer 5

Lacunae: tiny spaces that contain the osteocytes, or bone cells Canaliculi: small tunnels that connect one lacunae to another lacunae Lamellae: sheets of mineralized collagen that extend over hundreds of bone tissue Haversian canals: a series of tubes around narrow channels formed by lamellae

Answer 6

Ossification centers develop in the fibrous connective tissue membrane Osteoid is secreted and calcifies Immature spongy bone and periosteum form Compact bone replaces immature spongy bone just deep to the periosteum red marrow develops

Answer 7

Bone collar forms around the diaphysis of the hyline cartilage model Cartilage in the center of the diaphysis calcifies and then develops cavities The periosteal bud invades the internal cavities and spongy bone forms The diaphysis elongates and a medullary cavity forms secondary ossification centers appear in the epiphyses The epiphyses ossify when completed hyaline cartilage remains only in the epiphyseal plates and articular cartilages

Answer 8

Primary forms in the diaphyseal region of the periosteum Secondary ossification centers are located in the epiphyses

Answer 9

Begins with mesenchymal tissue transforming into a cartilage intermediate which is later replaced by bone and forms the remainder of the axial skeleton and the long bones

Answer 10

Proximal epiphysis Diaphysis Distal epiphysis

Answer 11

Articular cartilage Spongy bone Epiphyseal line Periosteum Medullary cavity lined by endosteum

Answer 12

Is a group of diseases in which bone resorption exceeds deposit Matrix remains normal, but bone mass declines Spongy bone of spine and neck of femur most susceptible Vertebral and hip fractures are common

Answer 13

Soft bones

Answer 14

A lack of vitamin D or calcium in a child's diet bowed legs and deformation of the pelvis, skull and ribcage are common

Answer 15

Disruption in normal remodeling Initially, old bone breaks down faster than new bone can be rebuilt later new bone is produced at a faster than normal rate more spongy bone Results in enlarged and deformed bones in one or more regions of the skeleton Cause unknown may be initiated by a virus

Answer 16

Support Protection Anchorage Mineral Storage Blood Cell Formation red bone marrow Storage of fats yellow marrow Hormone production osteocalcin

Answer 17

Hematopoiesis is the process by which the body produces blood cells It occurs in the hematopoietic system which includes organs and tissues such as the bone marrow liver and spleen

Answer 18

Organic Components 1/3 is osteoid ground substance proteoglycans and glycoproteins Collagen fibers provides flexibility and tensile strength

Answer 19

Inorganic Components 2/3 of matrix Mineral Salts hydroxyapatite calcium phosphate crystals Provides hardness and compression resistance weight bearing strength

Answer 20

Periosteum and endosteum are both layers of tissue that cover bones The periosteum covers the outer surface of bones while the endosteum lines the inner surface of the medullary cavity

Answer 21

Osteoblasts: bone cells that produce new bone tissue Lamellae: layers of tissue that form concentric circles around the osteon Central canal: a tube-like passage that contains blood vessels and nerve fibers Lacunae: small spaces that contain bone cells osteocytes

Answer 22

When an individual reaches skeletal maturity the growth of their long bones stops This happens because the cartilage in the epiphyseal plate which is the growth layer of a long bone is replaced by bone The chondrocytes in the epiphyseal plate divide during development and when they stop dividing the bone stops growing in length.

Answer 23

Thyroid hormone Estrogen and testosterone

Exam #3 Flashcards

(47 cards)