A&P Ch 7

Question 1

functions of the skeleton

Answer 1

support, protection, movement, electrolyte balance, acid-base balance, blood formation

Question 2

bones

Answer 2

bone tissue=osseous tissue=calcified CT. bones are made up of many tissues. osseous, nervous, fibrous ct and blood

Question 3

shapes of bones

Answer 3

long, short, flat, irregular

Question 4

long bone

Answer 4

femur, ulna, radius

Question 5

short bone

Answer 5

carpals, tarsals

Question 6

flat bone

Answer 6

scapula, sternum

Question 7

irregular bone

Answer 7

vertebrae

Question 8

features of bones

Answer 8

compact, spongy, articular, diaphysis, epiphysis, marrow cavity, periosteum, endosteum, epiphyseal plate, epiphyseal line

Question 9

compact bone features

Answer 9

outer layers of all bones, diaphysis of long bones

Question 10

spongy bone features

Answer 10

heads of long bones, middle of all others(diploe)

Question 11

articular features

Answer 11

covers joint surfaces, hyaline cartilage

Question 12

diaphysis features

Answer 12

shaft of a long bone

Question 13

epiphyses features

Answer 13

end of a long bone

Question 14

marrow cavity features

Answer 14

also called the medullary cavity. contains bone marrow

Question 15

periosteum features

Answer 15

has outer fibrous layer composed of collagen fibres. fibres may be continuous and bind to other bones via ligaments and muscles via tendons. has inner osteogenic layer composed of osteogenic cells and osteoblasts

Question 16

endosteum features

Answer 16

lines the medullary cavity. contains osteogenic cells and osteoblasts

Question 17

epiphysieal plate features

Answer 17

found in growing bones. separates marrow spaces btwn epiphysis and diaphysis of long bone. children

Question 18

epiphyseal line features

Answer 18

found in adult long bones. remnant of the epiphyseal plate

Question 19

osteogenic cells

Answer 19

(stem cells) origin=fibroblasts. location=edosteum lining medullary, trabeculae, central canals. periosteum lining the outside. lining the trabeculae throughout spongy bone. function=mitosis, some stay behind, some become osteoblasts

Question 20

osteoblasts

Answer 20

(build bones). origin= osteogenic cells. function= build bone, secrete collagen, alkaline phosphatase (raises pH so crystals form)

Question 21

osteocytes

Answer 21

mature osteocytes. origin=osteoblasts. location=surrounded by bone matrix. function=stress sensors. absorb nutrients, direct bone remodelling.

Question 22

osteoclasts

Answer 22

stem cells fuse together. origin=blood cells. location= same as osteogenic cells and osteoblasts. function= reabsorption of bone. secrete acid phosphatase to break down collagen, secrete HCl to break down Ca2+ crystals

Question 23

matrix

Answer 23

organic=provides flexibility, composed of collagen. inorganic=provides strength, hydroxyapatite. makes bones stuff.

Question 24

compact bone

Answer 24

osteon is the structural unit. collagen fibres are in alternating orientations to increase strength. fibres are organized in corkscrew pattern along length of bone. highly vascularized, nutrients flow from nutrient foramina through perforating canals to central canals and then from osteocyte to osteocyte via canaliculi

Question 25

spongy bone

Answer 25

found in epiphysis of long bones and in middle of all other bones. is a lattice of trabeculae with marrow in the spaces in btwn trabeculae. trabeculae are arranged along stress lines. strong but light. osteogenic cells and osteoblasts line the trabeculae

Question 26

bone marrow

Answer 26

found in medullary cavity and epiphyses of long bones and around trabeculae of spongy bone.

Question 27

red marrow

Answer 27

hemopoietic= produces all the blood cells. found in all spongy bone of children. found in axial skeletons & pevis, heads of femur, humerus of adults

Question 28

yellow marrow

Answer 28

produces blood cells only in chronic anemia

Question 29

endochondral ossification=bone elongation

Answer 29

most bones are produced this way. embryonic tissue(mesenchyme)->hyaline cartilage model-> bone.

Question 30

metaphysis

Answer 30

the transition between cartilage and bone at each end of the bone. occurs in fetus and until a person reaches final height.

Question 31

appositional growth

Answer 31

widening of the bone, occurs at the periosteum

Question 32

wolfs law of bone

Answer 32

bone adapts to stresses applied to it. strength of bone depends on use.