A&p Ch. 6

Front 1

What are the main functions of the skeletal system?

Back 1

support - structural framework, anchors soft tissues, provides attachments for tendons; protection - brain/cranium; movement - leverage for muscular contraction; storage - minerals (calcium,phosph), yellow marrow (adipose tissues/triglycerides); blood cell production - in red marrow, produces blood cells

Front 2

Define hemopoiesis and were does it occur?

Back 2

production of blood cells, occurs in: cranium, sternum ribs, vertebrae, humoral and femoral heads

Front 3

What is the difference between chondroblasts and chondrocytes?

Back 3

blasts - produce new cartilage matrix (has lacunae); cytes - maintains the cartilage

Front 4

Why does cartilage take a long time to heal?

Back 4

blood vessels and nerves are found only in the perichondrium and don’t enter the cartilage itself. Therefore, nutrients and oxygen diffuse through the cartilage matrix to the cells

Front 5

List and describe the two ways cartilage grows.

Back 5

appositional - layers on the outer surface by chondroblasts from inner perichondrium layer; interstitial - growth from within by chondrocytes dividing and production additional matrix.

Front 6

List and describe the three types of cartilage.

Back 6

hyaline - most abundant, ends of long bones/ribs, replaced by endochondrial ossification , strong, inflexible; fibrocartilage - tough, flexible, forms intervertebral discs, pubic symphysis; the matrix has a lot of collagen

Front 7

Define diaphysis.

Back 7

(length); shaft of the bone

Front 8

Define metaphysis.

Back 8

junction where diaphysis/epiphysis meet and where the growth plate is found.

Front 9

Define epiphysis.

Back 9

(end); the extremities or ends of bone.

Front 10

What is the growth plate?

Back 10

growth area of bone; originally hyaline cart; it connects the diaphysis/epiphysis in metaphysis.

Front 11

Define epiphyseal line.

Back 11

a boney structure (closed growth plate) that is found in adults.

Front 12

Define articular cartilage.

Back 12

hyaline cartilage covering the surface of the ends of bones; (articulations)

Front 13

Define periosteum.

Back 13

hard, outer membrane of the surface of bone.

Front 14

Define medullary cavity.

Back 14

space in the diaphysis that yellow marrow and red marrow (in some bones)

Front 15

Define endosteum.

Back 15

membrane lining the medullary cavity.

Front 16

What are osteochondral progenitor cells?

Back 16

These cells are stem cells, able to go through mitosis and eventually become osteoblasts or chondroblasts.

Front 17

Define osteoblasts.

Back 17

(build) cells that form bone but no longer can go through mitosis; secrete; material that will compose the matrix of the bone; derived from osteochondral cells

Front 18

Define osteocytes.

Back 18

(produce); mature bone cells that are derived from osteoblasts-they are the main cell of osseous tissue

Front 19

Define osteoclasts.

Back 19

(resorb); cells that settle on surfaces of bone and are responsible for resorptionor breakdown of the matrix

Front 20

Define osteogenesis.

Back 20

formation of new bone by osteoblasts

Front 21

What makes up a bone matrix?

Back 21

produced by osteoblasts; 15% water, 30% collagen, 55% calcium salts; is solid, composed of mostly calcium salts which are deposited in the framework of collagen fibers, giving flexibility to the hard inorganic material

Front 22

List and describe two types of bones.

Back 22

compact - bone tissue that is very tight and dense; composes the outside of all bones, contains osteons; spongy (cancellous) - arrangement of bone that consists of separate plates called trabeculae (spaces filed with marrow and blood vessels); makes up the internal portion of bones (hemoposis occurs here)

Front 23

Define ossification.

Back 23

process by which bone forms.

Front 24

What are the two types of ossification and in what bones are they found?

Back 24

intramembraneous: flat bones of skull, mandible and clavicles. endochondral: all other bones

Front 25

Describe intramembraneous ossification.

Back 25

occurs in: flat skull bones, mandible, clavicle; four steps - development of ossification center (clustering and differentiation of mesenchyme cells), calcification (extracellular matrix hardens), formation of trabeculea (forming spongy bone), periosteum development (superficial spongy bone is replaced with compact)

Front 26

Describe endrochondral ossification.

Back 26

occurs in: most other bones; six steps - development of the cartilage model (collection of mesenchyme cells), growth of cartilage model (length from interstitial growth, width from appositional growth), development of the primary ossification center (inward-bone tissue will replace most of cart.), development of the medullary cavity, development of the secondary ossification center (outward), formation of articular cartilage (hyaline becomes articular)

Front 27

What are the growth factors of bone?

Back 27

1) nutrition - calcium (dependent on Vit. D), Vit. C (important for collagen synthesis) 2) hormones - growth hormone (bone); thyroid (cartilage formation); estrogen/testosterone (growth spurts/stops); parathyroid/calcitonin (controls blood calcium levels) 3) genetics

Front 28

What is bone remodeling?

Back 28

the ongoing replacement of old bone tissue by new bone tissue

Front 29

Describe calcitonin and PTH in relation to bone remodeling.

Back 29

are both antagonistic hormones, and together will regulate the balance of calcium between the bone and the blood and are therefore vital in bone remodeling.

Front 30

What is PTH?

Back 30

hormone secreted by parathyroid glands, increases the blood calcium level by increasing the activity of osteoclasts. PTH is released in response to a low level of calcium in the blood; calcium is derived from bone.

Front 31

What is Calcitonin

Back 31

hormone secreted by the thyroid gland, decreases blood calcium levels by decreasing the activity of osteoclasts; . Calc is released in response to a high level of calcium in the blood; calcium is taken into the bone.

Front 32

What are the steps in bone repair?

Back 32

hematoma formation, callus formation, callus ossification, remodeling of bone

Front 33

Define hematoma.

Back 33

localized mass of blood confined within an organ or space

Front 34

Describe hematoma formation.

Back 34

fracture, broken blood vessels (which rushes to area, clot forms 6-8hrs after injury) - osteocytes around the site die due to a disruption of the blood/oxygen. inflammation occurs, bringing phagocytic cells and osteoclasts into the area to clean up dead/dying bone cells.

Front 35

Define callus.

Back 35

mass of tissue that forms at the fracture site and attempts to connect the broken ends of the bones

Front 36

Describe callus formation.

Back 36

the connective tissue mass will be invaded by chondroblasts from the periosteum and endosteum of the broken bone.

Front 37

Describe callus ossification.

Back 37

similar to fetal development, the chondrocytes will eventually be replaced by osteoblasts and new bone will be formed.

Front 38

Describe remodeling of bone.

Back 38

repair of the bony callus by osteoblasts and osteoclasts - for this to occur, 2 portions bone must be located very near to each other and held stationery. - if not ,another material must be used to join the bone – living bone from another site, dead bone from a cadaver

Front 39

What are the effects of exercise on bone?

Back 39

becomes stronger in response to mechanical stress.

Front 40

What are the effects of age on bone?

Back 40

a decrease in bone mass via reduction of estrogen (w/ menopause --> lower calcium deposits in matrix)/testosterone - decreased protein synthesis (decreased collagen = loss of flexibility = more fractures)

Front 41

Describe osteoporosis.

Back 41

porous bones characterized by decrease bone mass that are more likely to fracture - bone resorption occurs faster than bone formation (war b/w PTH and Calcitonin), effects middle age and older people, primarily women, young people w low caloric intake (eating disorders, low fat content) - commonly occurs in os coxa, intervertebral disks, femoral head/neck

Front 42

What's the first sign of osteoporosis?

Back 42

pathological spontaneous fracture (bone becomes so thin it cant take everyday stress)

Front 43

Describe rickets

Back 43

disease resulting from reduced mineralization of the bone matrix in children. (insufficient vitamin D)

Front 44

Describe osteomalacia.

Back 44

“adult rickets”; softening of the bones as a result of calcium depletion

Front 45

Describe scurvy.

Back 45

vitamin C deficiency causing a decrease of collagen synthesis leading to poor wound healing. (marked by ulceration and hemorrhage in almost any area of the body because of the lack of normal collagen synthesis in connective tissues)

Front 46

What is a fracture?

Back 46

any break in a bone

Front 47

What are the two types of fractures?

Back 47

simple (closed) & compound (open)

Front 48

Define greenstick fracture.

Back 48

partial fracture

Front 49

Define impacted fracture.

Back 49

one side of fracture driven into the interior of other side

Front 50

Define closed fracture.

Back 50

no break in skin

Front 51

Define open fracture.

Back 51

skin broken

Front 52

Define comminuted fracture.

Back 52

broken ends of bones are fragmented (shattered)

Front 53

Describe spiral fracture.

Back 53

fracture follows twisted line.

Front 54

Describe transverse fracture.

Back 54

horizontal break

Front 55

Describe pott's fracture.

Back 55

distal fibular fracture (rolling your ankle)

Front 56

Describe colle's fracture.

Back 56

distal radial fracture (wrist)

Front 57

Describe stress fracture.

Back 57

microscopic fissures from repeated strenuous activities

Front 58

What is vitamins A, C, D responsible for?

Back 58

A - remolding bone; C - collagen synthesis; D - helps build bone by increasing calcium absorption

Front 59

What hormone stops the growth of the skeletal system?

Back 59

sex hormones, estrogen and testosterone

Front 60

What is the precursor to bone?

Back 60

cartilage

Front 61

Define oblique fracture.

Back 61

a diagonal fracture.