Lecture 8 - Bone

Question 1

def: specialized connective tissue with calcified ECM

Answer 1

bone

Question 2

def: dense tissue, built to withstand compression

Answer 2

compact bone

Question 3

def: contains macroscopic open space, helps balance the strength of the bone against the weight of the skeleton

Answer 3

spongy/trabecular one

Question 4

at the end of the head of the femur, the bone forms part of a synovial joint and the outer cortical plate consists of __________ ______ _______

Answer 4

articular hyaline cartilage

Question 5

on the shaft of this long bone, the outer layer would be formed from ___________ ____________

Answer 5

fibrous periosteum

Question 6

between the bony trabeculae, there are _________ ___________

Answer 6

intervening spaces

Question 7

def: bone consists of a network of interconnecting struts orientated to provide maximum strength for the minimum mass

Answer 7

trabecular (cancellous bone)

Question 8

trabecular bone contains ____________ ___________ ___________

Answer 8

haematopoietic marrow spaces

Question 9

what does red marrow produce?

Answer 9

• red blood cells
• white blood cells
• platelets

Question 10

what does yellow marrow produce?

Answer 10

• fat
• cartilage
• bone

Question 11

____________ have only red bone marrow, _____________ marrow forms progressively with age

Answer 11

newborns, yellow

Question 12

where is red bone marrow in adults?

Answer 12

primarily located in the bones of the axial skeleton, like the head of the femur

Question 13

hematopoietic cells lie in intimate contact with numerous thin-walled blood vessels called _________-

Answer 13

sinusoids

Question 14

def: wider section at each end, made from a thin layer of compact bone and filled with spongy bone, red marrow fills the spaces in spongy bone

Answer 14

epiphysis

Question 15

def: cylindrical long portion of each long bone, with walls of compact bone

Answer 15

diaphysis

Question 16

def: the hollow inside of the diaphysis

Answer 16

medullary cavity

Question 17

def: dense irregular connective tissue membrane covering the other surface of most bones (except were synovial cartilage covers bone in joints)

Answer 17

periosteum

Question 18

def: contains both collagen and elastin, as well as blood vessels and nerves

Answer 18

fibrous layer

Question 19

def: contains both mature osteocytes and multi-potent precursors

Answer 19

cellular layer

Question 20

what does the periosteum do?

Answer 20

supplies blood to bone

Question 21

where are nociceptors in bone?

Answer 21

in the spongy bone

Question 22

def: microscopic structural units of compact bone, long, cylindrical structure with a central channel called a Haversian canal, containing blood vessels, lymphatics, and nerves

Answer 22

osteons

Question 23

def: each osteon contains concentric rings of this that forms in layers around a central Haversian canal

Answer 23

lamellar bone

Question 24

where do osteocytes reside?

Answer 24

lacunae

Question 25

def: prominent filopodia that extend through channels in the bone

Answer 25

canaliculi

Question 26

what are the traversing blood vessels in compact bone called?

Answer 26

volkman

Question 27

trabecular bone still grows in a laminar fashion, but lacks ________ and ____________ _______

Answer 27

osteons and Haversian canals

Question 28

canaliculi from lacunae in trabecular bone open to the surface of the ________________, allowing osteocytes to communicate with highly vascular bone marrow

Answer 28

endosteum

Question 29

def: regions between Haversian systems, remnants of older Haversian systems that have become highly mineralized

Answer 29

interstitial bone

Question 30

def: more intense staining of osteons compared to interstitial lamellae reflects their lower mineralization

Answer 30

india ink

Question 31

in India ink, the newest formed bone is stained how?

Answer 31

darker stained, it is non-mineralized, more permeable

Question 32

def: connect adjacent osteons in compact lamellar bone, such canals perforate lamellae and provide another source of microvasculature for the central canals of osteons

Answer 32

transverse perforating (Volkmann) canals

Question 33

def: maintains bone tissue

Answer 33

osteocyte

Question 34

def: forms bone matrix

Answer 34

osteoblast

Question 35

def: stem cells in bone

Answer 35

osteogenic

Question 36

def: resorbs bone

Answer 36

osteoclasts

Question 37

def: responsible for the synthesis of the organic components of bone matrix, consisting of type I collagen fibres, proteoglycans, and several glycoproteins including osteonectin

Answer 37

osteoblasts

Question 38

where are osteoblasts located?

Answer 38

exclusively at the surfaces of bone matrix, usually side by side in a layer somewhat resembling a simple epithelium

Question 39

active osteoblasts look like:

Answer 39

cuboidal to columnar shape and basophilic cytoplasm

Question 40

declining osteoblasts look like:

Answer 40

they flatten and cytoplasmic basophilia is reduced

Question 41

when bone matrix is actively proliferating, it is adding _____________

Answer 41

hydroxyapatite

Question 42

def: remain active cells, regulating the mineral content of the bony matrix, exhibit less RER, smaller Golgi complexes, more condensed nuclear chromatin than osteoblasts

Answer 42

osteocytes

Question 43

which has more euchromatin, an osteoblast or osteocyte?

Answer 43

osteoblast

Question 44

osteocytes are the ________ of bone, they act as mechano-sensors to mediate load-induced adaptation and govern the activity of osteoblasts and osteoclasts

Answer 44

mechano-stats

Question 45

def: very large, motile cells with multiple nuclei, arise from the fusion of hematopoietic progenitors in the bone marrow

Answer 45

osteoclasts

Question 46

def: enzymatically etched depressions or crypts in the matrix in areas of bone undergoing resorption

Answer 46

resorption bays

Question 47

def: appropriate remodelling to preserve bone health and function, is a product of the balanced activity of osteoclasts and osteoblasts

Answer 47

bone homeostasis

Question 48

def: disease in which bone resorption outpaces bone replacement

Answer 48

osteoporosis

Question 49

def: stone bones, mutation in osteoclasts inhibits normal bone resorption

Answer 49

osteopetrosis

Question 50

def: brittle bone disease, multiple mutations, all affective Type I collagen production

Answer 50

osteogenesis imperfecta

Question 51

def: osteoclasts and osteoblasts work on opposite surfaces of bone to shape the bone in one direction

Answer 51

bone modelling

Question 52

def: osteoclasts and osteoblasts work on the same surface of bone to digest old bone and replace it with new bone

Answer 52

bone remodelling