Bones ch6

Question 1

functions of skeletal system

Answer 1

support, storage of minerals, storage of lipids, blood cell production, protection, leverage

Question 2

bones are classified by

Answer 2

shape, internal tissue organization, bone markings

Question 3

long bones

Answer 3

long and thin; found in arms, legs, hands, feet, fingers, toes

Question 4

flat bones

Answer 4

thin with parrallel surfaces; skull, sternum, ribs, scapulae

Question 5

irregular bones

Answer 5

complex shapes, spinal vertebrae, pelvic bones

Question 6

short bones

Answer 6

small and thick; ankle and wrist bones

Question 7

sesamoid bone

Answer 7

not directly connected to other bones, develop inside tendons; patella

Question 8

depressions or grooves

Answer 8

points of attachment

Question 9

projections

Answer 9

where tendons and ligaments attach; articulation with other bones

Question 10

tunnels

Answer 10

where blood and nerves enter bone

Question 11

long bone structure (3 parts)

Answer 11

diaphysis, epiphysis, metaphysis

Question 12

diaphysis

Answer 12

the shaft; heavy wall of compact bone, central space called medullary cavity (marrow)

Question 13

epiphysis

Answer 13

wide part at ends, articulation with other bones, mostly spongy bone covered with compact bone

Question 14

metaphysis

Answer 14

where diaphysis and epiphysis meet; hyaline cartilage until adulthood

Question 15

flat bone structure

Answer 15

sandwich of spongy bone between two layers of compact bone

Question 16

diploe

Answer 16

spongy bone in the cranium

Question 17

membranes of bone

Answer 17

periosteum, endosteum

Question 18

periosteum

Answer 18

outer fibrous layer with inner osteogenic layer: osteoblasts, osteoclasts, osteogenic cells (stem cells)

Question 19

periosteum (nutrient and securement)

Answer 19

nerve fibers, blood vessels and lymphatic vessels via nutrient foramina; secured to bone by collagen and sharpey’s fibers

Question 20

endosteum

Answer 20

delicate membrane on internal surface of bone, osteoblasts and osteoclasts; covers trabeculae and lines canals

Question 21

red marrow cavities of adults

Answer 21

trabecular cavities of heads of femur and humerus and diploe of flat bones

Question 22

red marrow cavities of children

Answer 22

medullary cavities and all spaces in spongy bones

Question 23

osteocytes

Answer 23

Bone Maintainers: mature bone cells that maintain the bone matrix, live in lacunae, monitor and maintain mineral content and repair damage bone

Question 24

osteoblasts

Answer 24

Bone Makers: immature bone cells that secrete matrix compounds (osteogenesis); if surrounded by bone they become osteocytes

Question 25

osteoid

Answer 25

matrix produced by osteoblasts, but not yet calcified to form bone

Question 26

osteoclasts

Answer 26

Bone Breakers: secret acids and protein digesting enzymes, giant multinucleate cells, dissolve bone matrix and release stored minerals (osteolysis); derived from stem cells that produce macrophages

Question 27

Osteoprogenitor Cells

Answer 27

mesenchymal stem cells that divide to produce osteoblasts, located in the endosteum and inner cellular layer of periosteum; assist in fracture repair

Question 28

homeostasis

Answer 28

bone making must balance with bone recycling

Question 29

Anatomy of compact bone (osteon) 5

Answer 29

lamellae, central canal, perforating canal (volkmann), lacunae, canaliculi

Question 30

Anatomy of spongy bone

Answer 30

open network of trabeculae, irregularly arranged lamellae, osteocytes and canaliculi; no osteon or central canal; red or yellow marrow

Question 31

organic composition of bone

Answer 31

osteogenic, blasts, clasts, cytes, osteoid, proteoglycans, glycoproteins, collagen fibers

Question 32

inorganic composition of bone

Answer 32

hydroxyapatites: mineral salts (65% of mass) mainly calcium phosphate,

Question 33

mineral salts

Answer 33

responisble for hardness and resistance of compression

Question 34

intramembranous ossification

Answer 34

from fibrous membranes (mesenchyme); flat bones; 1) mesench cluster 2) diff in to osteoprogen 3) divide to become osteoblasts

Question 35

endochondral ossification

Answer 35

originate as hyaline cartilage; most bones except flat, 6 main steps:

Question 36

interstitial vs apositional

Answer 36

increase the length vs. increase the thickness, remodeling of surfaces

Question 37

epiphyseal plate cartilage 4 zones

Answer 37

proliferation (cartilage dividing), hypertrophic (increase size), calcification, ossification

Question 38

hormones

Answer 38

growth hormones, thyroid hormones, testosterone and estrogen

Question 39

wolfs law

Answer 39

greater stress= more bone deposition; support: handedness, curved bones, trabeculae, bony projections

Question 40

bone remodeling

Answer 40

osteoclasts break down bone: lysosomal enzymes and acids; osteoblasts deposit; replaces minerals, recycles and renews matrix;

Question 41

effects of excercise on bone

Answer 41

bones adapt to stress, stress makes thicker and stronger

Question 42

bone nutrition

Answer 42

calcium, phosphate salts, small amt of magnesium, fluoride, iron and manganese; hormone calcitrol; vitamin d

Question 43

calcium

Answer 43

most abundant mineral in the body, ions are vital to membranes, neurons, muscle cells (heart)

Question 44

calcium homeostasis

Answer 44

calcitonin/thyroid (too much) and parathyroid hormone (too little), controls storage (bones) absorption (Dig) and excretion (kid)

Question 45

osteomalacia and rickets

Answer 45

when calcium salts are not deposited, caused by vit d or calcium deficiency

Question 46

osteopenia

Answer 46

general bone loss, thinner and weaker with age, starts 30-40, women lose 8% per decade, men 3%; epiphyses, vertebra and jaws mostly

Question 47

osteoporosis

Answer 47

severe bone loss, over 45, 29% of women, 18% men

Question 48

osteoporosis treatment

Answer 48

ca, vD, fluoride supplements; weight bearing excercise, hormone replacement therapy slows loss