Bone Tissue

Front 1

FUNCTIONS OF BONE

Back 1

1. support
2. protection
3. assistance in movement
4. mineral homeostasis
5. blood cell production (hemopoiesis)
6. triglyceride storage

Front 2

STRUCTURE OF LONG BONE

Back 2

1. diaphysis
2. epiphyses
3. metaphyses
4. articular cartilage
5. periosteum
6. medullary cavity
7. ENDOSTEUM

Front 3

DIAPHYSES

Back 3

- bone' shaft or body

Front 4

EPIPHYSES

Back 4

- proximal and distal ends of the bone

Front 5

METAPHYSES

Back 5

- between diaphysis and epiphysis; in a growing bone contains an epiphyseal plate (allows the diaphysis to grow in length)

Front 6

ARTICULAR CARTILAGE

Back 6

- covers the part of the epiphysis where the bone forms an articulation (joint) with another bone
- recues friction and absorb shock at freely movable joints

Front 7

PERIOSTEUM

Back 7

- tough connective tissue sheath and its associate blood supply
- surround the bond surface whenever it is not covered by articular cartilage
-may enable to grow in thickness
- protects bone, assists in fracture repair, nourish bone tissue, attachment point for ligaments and tendons

Front 8

MEDULLARY CAVITY

Back 8

- within the diaphysis
- contains fatty yellow bone marrow and blood vessels
- minimises the weight of the bone

Front 9

ENDOSTEUM

Back 9

lines the medullary cavity

Front 10

CALCIFICATION

Back 10

formed crystals they combine with other mineral salts and ions -> deposited in the framework formed by the collagen fibers of the extracellular matrix they cristalize and the tissue hardens

Front 11

CELLS IN BONE TISSUE

Back 11

1. osteogenic cells
2. osteoblasts
3. osteocytes
4. osteoclasts

Front 12

OSTEOGENIC CELLS

Back 12

- unspecialised bone stem cells derived from mesenchyme
- go cell division! the resulting cells develop into osteoblasts

Front 13

OSTEOBLASTS

Back 13

synthesise and secrete collagen and other organic components needed to build the extracellular matrix of bone tissue
Build bone
as they surround themselves with extracellular matrix they form osteocytes

Front 14

OSTEOCYTES

Back 14

mature bone cells
maintain metabolism

Front 15

OSTEOCLASTS

Back 15

concentrated in the endosteum
RESORPTION - the breakdown of bone extracellular matrix (development, maintenance, repair of bone)
Curve out bone

Front 16

COMPACT BONE TISSUE

Back 16

the strongest form
found beneath the periosteum and make up the bulk of the diaphyses of long bones
Protection and support and resist stresses
Composed of osteons
The lines of stress can change in response to the physical demands placed on the skeleton

Front 17

INTERSTITIAL LAMELLAE

Back 17

fragments of older osteons that have been partially destroyed during bone rebuilding and growth

Front 18

VOLKMANN'S CANALS

Back 18

blood vessels, lymphatic vessels, nerves from periosteum penetrate the compact bone through Volkmann's canals

Front 19

SPONGY BONE TISSUE

Back 19

no osteons
in the interior of a bone
Protected by covering of compact bone
Where bones are not heavily stressed or where stresses are applied from many directions

Front 20

TRABECULAE

Back 20

lamellae arranged in an irregular pattern of thin columns in spongy bone tissue
Final arrangement when location is learned

Front 21

BLOOD AND NERVE SUPPLY OF BONE

Back 21

1. periosteal arteries in and veins out
2. metaphyseal arteries in and veins out
3. epiphyseal arteries in and veins out

Front 22

PERIOSTEAL ARTERIES

Back 22

enter the diaphysis through many Volkmann's canals
Supply the periosteum and outer part of the compact bone

Front 23

METAPHYSEAL ARTERIES

Back 23

enter the metaphyses of a long bone
Supply the red bone marrow and bone tissue of the metaphyses

Front 24

EPIPHYSEAL ARTERIES

Back 24

enter the epiphyses of a long bone
Supply the red bone marrow and bone tissue of the epiphyses

Front 25

OSSIFICATION

Back 25

a process in which a bone is formed

Front 26

BONE FORMATION IN AN EMBRYO AND FETUS

Back 26

1. intramembranous ossification
2. endochondral ossification

Front 27

INTRAMEMBRANOUS OSSIFICATION

Back 27

flat bones of the skull, facial bones, medial part of the clavicle,

Involves the formation of bone within mesenchyme arranged in sheetlike layers that resemble membranes

Front 28

ENDOCHONDRAL OSSIFICATION

Back 28

the replacement of cartilage by bone

Front 29

BONE GROWTH DURING INFANCY CHILDHOOD AND ADOLESCENCE

Back 29

1. in length
2. in thickness

Front 30

GRWOTH IN LENGTH

Back 30

1. interstitial growth of cartilage on the epiphyseal side of the epiphyseal plate
2. Replacement of cartilage on the diaphyseal side of the epiphyseal plate with bone by endochondral ossification

Front 31

EPIPHYSEAL PLATE

Back 31

layer of hyaline cartilage in the metaphysis of a growing bone

Front 32

4 ZONES OF EPIPHYSEAL PLATE

Back 32

1. resting cartilage
2. proliferating cartilage
3. hypertrophic cartilage
4. calcified cartilage

Front 33

RESTING CARTILAGE

Back 33

does not function in bone growth
Anchor the epiphyseal plate to the epiphysis of the bone

Front 34

PROLIFERATING CARTILAGE

Back 34

chondrocytes undergo interstitial growth as they divide and secrete extracellular matrix
Chondrocytes divide to replace those that die at the diaphyseal side of the epiphyseal plate

Front 35

HYPERTROPHIC CARTILAGE

Back 35

maturing chondrocytes arranged in columns

Front 36

CALCIFIED CARTILAGE

Back 36

dead chondrocytes
calcified extracellular matrix
Osteoclasts dissolve the calcified cartilage and osteoblasts and capillaries from the diaphysis invade the area

Front 37

EPIPHYSEAL LINE

Back 37

when epiphyseal plate fades
Bony structure - formed when adolescence comes to an end

Front 38

GROWTH IN THICKNESS

Back 38

only by appositional growth
1. bone ridges on either side of a periosteal blood vessel
2. ridges fold together and fuse; tunnel that encloses blood vessel lined by the endosteum
3. the tunnel fills in - new osteon is created
4. osteoblasts deposit new circumferential lamellae and so on.....

Front 39

REMODELLING OF BONE

Back 39

ongoing replacement of old bone tissue by new bone tissue

Front 40

BONE RESORPTION

Back 40

removal of minerals and collagen fibers from bone by osteoclasts

Results in the destruction of bone extracellular matrix

Front 41

BONE DEPOSITION

Back 41

addition of minerals of collagen fibers to bone by osteoblasts
Results in the formation of bone extracellular matrix

Front 42

PAGET'S DISEASE

Back 42

excessive proliferation of osteoclasts

Front 43

FACTORS AFFECTING BONE GROWTH AND REMODELLING

Back 43

1. minerals
2. Vitamins
3. hormones

Front 44

MINERALS FOR BONES

Back 44

calcium and phosphorous and small magnesium, fluoride, and manganese for growth and remodelling

Front 45

VITAMINS FOR BONES

Back 45

A stimulates activity of osteoblasts
C synthesis of collagen
D building bone; increases the absorption of calcium
K and B12 synthesis of bone proteins

Front 46

HORMONES

Back 46

IGF - produced by liver and bone tissue (childhood); stimulates osteoblasts , promote cell division and synthesis of the proteins needed to build new bone

Thyroid hormones - stimulates osteoblasts

Insulin - increase the synthesis of bone proteins

Front 47

FRACTURES

Back 47

1. Open
2. Comminuted
3. greenstick
4. impacted
5. pott
6. colles

Front 48

REPAIR OF A BONE FRACTURE

Back 48

1. formation of fracture hematoma
2. fibrocartilaginous callus formation
3. bony callus formation
4. bone remodelling

Front 49

FRACTURE HEMATOMA

Back 49

mass of blood formed around the site of the fracture;
Nearby cells die and debris cause inflammation

Front 50

FIBROCARTILAGINOUS CALLUS FORMATION

Back 50

a mass of repair tissue consisting of collagen fibers and cartilage that bridges the broken ends of the bone

Front 51

BONY CALLUS

Back 51

converted spongy bone from the fibrocartilage

Front 52

CALCIUM HOMEOSTASIS

Back 52

Ca2+ is regulated by hormones (mimp PTH)
PTH acts on kidneys to decrease loss of Ca in the urine and stimulates formation of calcitriol - hormone that promotes absorption of Ca

Calcitonin (CT) - inhibits activity of osteoclasts speeds blood Ca uptake by bone and accelerates Ca deposition into bones