Histology - Hard Connective Tissue

Question 1

what are the fuctions of bones?

Answer 1

mechanical functions, haematopoesis, calcium homeostasis

Question 2

what is haematopoesis?

Answer 2

formation of blood components

Question 3

what is the principle of section modulus?

Answer 3

increasing the cross section of an object but with the same amount of material (making it hollow) increases bending resistance

Question 4

what does using composite materials do?

Answer 4

combines strengths in compression and tension resistance –> makes an overall stronger structure

Question 5

what is strain relief?

Answer 5

when two different materials connect to each other, there is stess concentrated at the discontinuity. spreading out the material so the shift from one material to the next is gradual spreads out the stress and makes a stronger connection

Question 6

what is the point to making bones hollow?

Answer 6

increases section modulus, reduces energy needed to make and maintain bone, reduce the amount of energy needed to hold bones up by muscle

Question 7

what is corticol bone?

Answer 7

solid bone on the outer surface of the bone

Question 8

what is trabecular bone?

Answer 8

the spongy bone inside of the corticol bone

Question 9

what is the main organic material in bone?

Answer 9

collagen (type I)

Question 10

what is the main inorganic material in bone?

Answer 10

hydroxyapatite

Question 11

what does collagen do in bone?

Answer 11

resists tensile forces

Question 12

what does hydroxyapatite do in bone?

Answer 12

resists compressive forces

Question 13

what are osteocytes?

Answer 13

cells that maintain bone tissue

Question 14

what are osteoblasts?

Answer 14

cells that create new bone

Question 15

what are osteoclasts?

Answer 15

cells that get rid of bone

Question 16

what is Howship’s lacunus?

Answer 16

the space around an osteoclast

Question 17

what is the arrow pointing to?

Answer 17

osteoclast

Question 18

what is apposition?

Answer 18

bone added on top of existing bone

Question 19

how does bone grow?

Answer 19

apposition

Question 20

where does bone growth occur?

Answer 20

on growth plates near the ends of bone

Question 21

what does removing calcium from bone do?

Answer 21

removes resistance to compression –> bone becomes very rubbery and soft

Question 22

what is woven bone?

Answer 22

created when osteoblasts make bone rapidly

no real orientation to material/fibers

Question 23

what type of bone are antlers made out of? why?

Answer 23

woven bone

they grow super fast

Question 24

what type of bone is this?

Answer 24

woven bone

Question 25

what is lamellar bone?

Answer 25

created when osteoblasts make bone slowly and put materials in a proper orientation stronger

Question 26

what type of bone is this?

Answer 26

lamellar/Haversian bone

Question 27

what is intramembranous bone?

Answer 27

bone formed directly in a membrane

Question 28

what is the advantage to intramembranous bone? what is the disadvantage?

Answer 28

quicker because it starts in multiple places and comes together cannot load bear while bone is growing

Question 29

what is this picture showing?

Answer 29

intramembranous bone formation

Question 30

what is endochondral bone?

Answer 30

bone that forms from a cartilaginous precursor

Question 31

what type of cartilage is involved in endochondral bone?

Answer 31

hyaline cartilage

Question 32

what is this photo showing? what are the letters pointing to?

Answer 32

endochondral bone formation A: proliferation zone (bone growth) B: maturation and hypertrophy (normal cells) C: calcified matrix (cell death) D: zone of ossification (metaphysis)

Question 33

what is another name for growth plates?

Answer 33

epiphyseal cartilages

Question 34

how does primary bone modelling work?

Answer 34

1. bone formation at the surface of bone produces ridges that paralell a blood vessel 2. ridges enlarge and create a deep pocket 3. the ridges meet and fuse, trapping the vessel inside the bone

Question 35

what is this photo showing? what is the black arrow pointing to? what is structure A?

Answer 35

mature lamellar bone arrow: blood vessel in central canal A: osteocyte

Question 36

what is the Bone Multicellular Unit (BMU)? what is the function of it?

Answer 36

unit with osteoclasts at the front and osteoblasts at the back resorb and lay down new bone

Question 37

what is a Haversian canal?

Answer 37

hole in the middle of an osteon where the BMU passed through

Question 38

what is an osteon?

Answer 38

how bone is laid down by BMUs concentric circles with a hole in the middle

Question 39

what is Volkmann's canal?

Answer 39

lateral branches of the circulatory system

Question 40

what is this photo showing? what do the letters mean?

Answer 40

remodelled bone A: osteon B: Volkmann's canal C: Haversian canal

Question 41

what is periosteum?

Answer 41

connective tissue around the outside of bones

Question 42

what is endosteum?

Answer 42

connective tissue lining Haversian canals

Question 43

label this photo

Answer 43

A: endosteum B: periosteum

Question 44

what is bone marrow?

Answer 44

gelatinous tissue that fills trabecular bone

Question 45

what are the types of bone marrow?

Answer 45

red and yellow

Question 46

what does red marrow do?

Answer 46

create RBCs, WBCs, platelets, endothelium, mesenchyme

Question 47

what does yellow marrow do?

Answer 47

create cartilage, fat, bone

Question 48

what do stromal cells do?

Answer 48

fix matrices

Question 49

what does red marrow contain?

Answer 49

hematopoeitic stem cells, mesenchymal stem cells, endothelial stem cells, stromal/dendridic cells, megakaryocytes

Question 50

what does yellow marrow contain?

Answer 50

stromal cells, adipocytes

Question 51

what are trabeculae?

Answer 51

projections of bone inside trabecular bone that hold things together

Question 52

what is this picture showing? label it

Answer 52

A: megakaryocyte B: adipocyte C: haematopoeitic and meylopoeitic cells

Question 53

what is this photo showing? label it

Answer 53

A: bone B: tendon C: calcified fibrocartilage D: fibrocartilage E: mineralization front showing tendon insertion into bone