osteology

Question 1

skeletal system is composed of…

Answer 1

bones, cartilage, and ligaments

Question 2

cartilage

Answer 2

precursor for most bones. cover joint surfaces

Question 3

ligaments

Answer 3

holds bone to bone together

Question 4

tendons

Answer 4

attaches muscle to bone

Question 5

functions of the skeletal system

Answer 5

provides structure/support, protection, site of blood cell formation, essential for movement, storage of minerals

Question 6

bone marrow

Answer 6

softer connective tissue that fills the interior of most bone

Question 7

why is bone marrow important?

Answer 7

serves as a site for fat storage and blood cell production

Question 8

yellow marrow

Answer 8

contains adipose (fat) tissue + serve as a source of energy

Question 9

red marrow

Answer 9

location of blood cell production (RBCs, WBCs, + platelets)

Question 10

hematopoiesis

Answer 10

the production of blood cells

Question 11

how many bones are in an adult skeleton?

Answer 11

206 bones

Question 12

long bones

Answer 12

longer than wide, cylindrical, used for leverage

Question 13

what type of bone does hematopoiesis occur in children?

Answer 13

long bones

Question 14

short bones

Answer 14

roughly cube shaped, found where stability/support/mobility is needed

Question 15

flat bones

Answer 15

thin bones, broad surface for muscle attachment

Question 16

what type of bone does hematopoisis occur in adults?

Answer 16

flat bones

Question 17

irregular bones

Answer 17

irregular shapes with numerous projections

Question 18

pneumatic bones

Answer 18

contain air spaces (sinuses), reduce the weight of the skull

Question 19

sesamoid bones

Answer 19

small round bones embedded within a tendon

Question 20

axial skeleton

Answer 20

bones of the skull, hyoid, vertebral column, and rib cage

Question 21

how many bones are in the axial skeleton?

Answer 21

80 bones

Question 22

appendicular skeleton

Answer 22

bones of the limbs, pectoral girdle, and pelvic girdle

Question 23

how many bones are in the appendicular skeleton?

Answer 23

126

Question 24

cranial skeleton

Answer 24

bones of the skull

Question 25

post-cranial skeleton

Answer 25

bones of the vertebral column

Question 26

how many bones are in the skull?

Answer 26

22 individual bones

Question 27

how many cranial bones?

Answer 27

8

Question 28

how many facial bones?

Answer 28

14

Question 29

disphysis

Answer 29

body/shaft of the bone

Question 30

where is the primary center of ossification (in utero)?

Answer 30

diaphysis

Question 31

epiphysis

Answer 31

ends of the bones that articulate with different bones

Question 32

where is the secondary center of ossification (in puberty)?

Answer 32

epiphysis

Question 33

metaphysis

Answer 33

where diaphysis and epiphysis meet

Question 34

epiphyseal plate

Answer 34

connects diaphysis to epiphysis. composed if hyaline cartilage

Question 35

what is another name for the epiphyseal plate?

Answer 35

growth plate

Question 36

periosteum

Answer 36

fibrous structure covering outer bone surfaces

Question 37

where is the periosteum absent?

Answer 37

articular bone surfaces + where tendons/ligaments attach

Question 38

periosteum layers

Answer 38

fibrous and cellular

Question 39

fibrous layer of periosteum

Answer 39

superficial. sheets of dense irregular connective tissue

Question 40

what is in the connective tissue of the fibrous layer?

Answer 40

type 1 collagen fibers, fibroblasts, blood vessels, lymph vessels, nerve fibers

Question 41

cellular layer of periosteum

Answer 41

deep. thin layer containing bone cells

Question 42

endosteum

Answer 42

thin connective tissue layer covering inner bone surfaces

Question 43

what type of bone cells are in endosteum?

Answer 43

osteoprogenitor cells + osteoblasts

Question 44

medullary cavity

Answer 44

cavity at the center of long bones. aka marrow cavity

Question 45

articular cartilage

Answer 45

hyaline cartilage covering articular/facet surfaces

Question 46

woven bone

Answer 46

newly calcified. develops when a fetus and when repairing a fracture

Question 47

what is another name for woven bone?

Answer 47

primary bone

Question 48

spongy/trabecular bone

Answer 48

inner layer of porous bone. located at the end of long bones

Question 49

compact/cortical bone

Answer 49

outer layer of densely packed bone tissue. contains haversian system

Question 50

spongy/cancellous/trabecular bone

Answer 50

in the interior of bone

Question 51

subchondral bone

Answer 51

very thin layer of modified compact bone

Question 52

where is subchondral bone found?

Answer 52

underlying articular cartilage

Question 53

osteons (haversian system)

Answer 53

cylindrical units of bone tissue, packed together tightly

Question 54

lamellae

Answer 54

concentric layers of bone tissue

Question 55

central canal

Answer 55

contains vascular structures and nerves

Question 56

lacunae

Answer 56

holes between lamellae

Question 57

canaliculi

Answer 57

passages connecting lacunae to each other

Question 58

perforating/communicating/volkmann's canals

Answer 58

connecting central canals together

Question 59

circumferential lamellae

Answer 59

multiple sheet-like layers of bone tissue

Question 60

external circumferential lamellae

Answer 60

located immediately deep to the periosteum

Question 61

inner circumferential lamellae

Answer 61

located at the perimeter of the medullary cavity

Question 62

interstitial lamellae

Answer 62

layers of bone tissue, between osteons

Question 63

bone matrix fibers

Answer 63

90% type 1 collagen, 10% ground substance

Question 64

bone salts

Answer 64

inorganic component in bones

Question 65

what are the most common bone salts?

Answer 65

calcium + hydroxyapatite

Question 66

purpose of bone salts

Answer 66

provides strength to resist compressive forces

Question 67

what type of strength do collagen fibers provide?

Answer 67

tensile strength

Question 68

osteoprogenitor cells

Answer 68

bone stem cell. give rise to osteoblasts

Question 69

osteoblasts

Answer 69

build new bone

Question 70

osteocytes

Answer 70

former osteoblasts that maintain bone tissue + mineral content

Question 71

osteoclasts

Answer 71

destroy bone

Question 72

what does bonding between collagen + hydroxyapatite prevent?

Answer 72

bone shearing/sliding

Question 73

place bone calcification steps in order of how they occur... 1. collagen monomers polymerize to form collagen fibers 2. osteoblasts secrete collagen molecules + ground substance 3. nidi multiply and grow 4. amorphous calcium salts are remodeled into hydroxyapatite crystals 5. calcium salts precipitate in osteoid 6. nidi of amorphous compounds form at intervals

Answer 73

2, 1, 5, 6, 3, 4

Question 74

place bone remodeling steps in order of how they occur... 1. enzymes digest/dissolve organic matrix of bone 2. osteoclasts embed small particles of bone and crystals by phagocytosis 3. osteoclasts eat bone away to create a tunnel 4. osteoclasts send out villus-like projections 5. acids dissolve bone salts 6. new bone begins to develop 7. villi-like projections secrete proteolytic enzymes + acids

Answer 74

4, 7, 1, 5, 2, 3, 6

Question 75

what does pyrophosphate inhibit?

Answer 75

hydroxyapatite crystallization + bone calcification

Question 76

endochondral ossification

Answer 76

bone formed from preexisting cartilage

Question 77

interstitial growth

Answer 77

growth of bones in length occuring at epiphyseal plate

Question 78

appositional growth

Answer 78

growth of bone in thickness/width

Question 79

intramembranous ossification

Answer 79

bone formed from connective tissue

Question 80

what stops bone growth?

Answer 80

human growth hormone

Question 81

wolff's law

Answer 81

bone remodels its shape according to the way force is transmitted through it