1. Ch. 6 Bone Tissue & The Skeletal System

2. Please Read Ch. 6 through bone tissue and use the information from Ch
Please Read Ch. 6 through bone tissue and use the information from Ch. 6 to fill in the ppt for the Terms below. ALSO: Study the bones on the word document entitled “Bone Assignment after Test ”
Give functions & locations of the 3 types of cartilage
Define Axial and Appendicular Skeletons & describe the 5 functions of the Skeletal System
Give a brief description of long, short, flat, irregular, and sesamoid bones
Define the Bone Marking Classifications: articulations (for joints), projections, and holes (depressions and openings)
Give the functions of the following cell types: osteogenic, osteoblasts, osteoclasts, osteocytes
Describe the following Bone Tissue items that we previously did in Ch. 4 again: osteon, haversian canal, volkmann’s canal, lacuna, canaliculi, and the lamella that are part of the osteon
How are circumferential and interstial lamella different from the lamella in osteons-- describe

3. I. Introduction Describe the skeletal cartilages and how they grow.
A. Parts: bones, cartilage, joints
Skeletal Cartilages
Perichondrium
Types
Growth
Appositional
Interstitial
Classification
Divisions
Axial
Appendicular
- 206 Bones
Describe the divisions of the Skeletal System.
Figure 6.1

4. Describe the bone shape categories and give their general functions.
2. Bone Classification by Shape * See Textbook Table for general functions of each
Describe the bone shape categories and give their general functions.
(e) Sesamoid bone
Figure 5.1

5. D. The Functions of The Skeletal System
Objectives
List and describe the functions of the Skeletal System 1. 2. 3. 4.
5. Minerals

6. II. Bone Structure A. Gross Anatomy 1. Bone Markings
* see Table in Textbook
a. Articulations
b. Projections
c. Depressions & Openings
2. Bone Textures
a. Compact Bone
b. Spongy Bone- Diploë
3. Gross Anatomy of a
Long Bone

7. II. Bone Structure … A. Gross Anatomy … 1. Bone Markings …
Table 6.1

8. 3. Structure of a Long Bone
A. Gross Anatomy …
3. Structure of a Long Bone
a) Epiphysis =
Type bone”
Epiphysial plate
Epiphyseal line
b) Diaphysis =
Type bone:
Medullary cavity & contents:

9. e) Articular Cartilage
c) Periosteum =
Structure/Composition:
Overall Function:
Nutrient foramen
d) Endosteum =
e) Articular Cartilage

10. 4. Structure of Short, Irregular & Flat Bones
A. Gross Anatomy …
4. Structure of Short, Irregular & Flat Bones
Spongy bone: Location
Compact bone: Location
Figure 5.2b

11. Bone Structure … B. Microscopic Anatomy
1. Cells of Bone Tissue
a. Osteogennic cells =
Turn into:
b. Osteoblasts – make:
c. Osteoclasts (derived from WBCs)
d. Osteocytes
Location
Function

12. d. Osteocytes …
Communicate:
Can sense stress in bone, then:

13. 2. Bone Tissue
a) Compact Bone
Function
Osteons = Haversian System
Haversian, Central Canal
Volkmann’s or Perforating Canals
Lacuna
Canaliculi
Osteon

14. a) Compact Bone … Osteons …
Lamella
In Osteon
Interstitial lamellae:
Circumferential lamellae:
Osteon
Figure 6.6a

15. 2. Bone Tissue …
b) Spongy Bone
Trabeculae
Function

16. C. Chemical Composition of Bone
Organic
Cells
Osteoid
2. Inorganic-- Hydroxyapatites
Ground Substance
Proteoglycans & glycoproteins
Collagen Fibers
Osteoid = newly secreted Ground &
Collagen
Inorganic
Ca-Phosphate = hydroxyapatites = 65%

17. III. Bone Formation and Development
Introduction
Embryo–most Skeleton Tissue:
Also some:
Ossify, Ossification:
Two Methods (Pathways
* Intramembraneous–
* Endochondral–
2. Baby Childhood  Late Teens
Still have Intramembraneous & Endochondral Development
*Child: Growth in height at cartilage only
3. Early Adulthood  Old Age
Growth in height ends
Only *Remodeling

18. 1. Ossification Center appears Mesenchyme cells:
Bone Formation and Development … A. Intramembranous Ossification Types of Bones:
1. Ossification Center appears
Mesenchyme cells:
They differentiate into:
Osteoblasts forms an Ossification Center
2. Bone Matrix (Osteoid) is Secreted and then ossifies
Osteoblasts secrete osteoid
Osteoid calcifies
Osteoblasts
Osteoblasts are now:
Figure 6.7.1

19. 3. Woven Bone and Periosteum Forms
Woven Bone: Osteoid laid down randomly around blood vessels = Trabeculae
Periosteum forms from vascularized mesenchyme
4. Lamellar Bone Replaces Woven Bone & Red Marrow Appears
Trabeculae are replaced w/ lamellar Bone = compact bone plartes
Spongy Bone is internal; forms red Marrow
Figure 6.7.3

20. A. Intramembranous Ossification … 4. Mature Bone Formed …
At Birth have Fontanels
Function:
Last Bones to Ossify:
Figure 6.7.4

21. B. Endochondral Ossification Type of Bones Cartilage Model
Perichondrium  Periosteum
Slide 7
Articular
cartilage
Secondary
ossification
center
Spongy
bone
Epiphyseal
blood vessel
Area of
deteriorating
cartilage matrix
Epiphyseal
plate
cartilage
Hyaline
cartilage
Spongy
bone
formation
Medullary
cavity
Bone collar
Blood
vessel of
periosteal
bud
Primary
ossification
center 1 2 3 4 5
Childhood to
adolescence
Week 9
Month 3
Birth
Figure 6.8 Endochondral ossification in a long bone.
© 2013 Pearson Education, Inc.

22. Bone Collar Forms Around Cartilage Mode
Endochondral Ossification …
Bone Collar Forms Around Cartilage Mode
Osteoblasts from Periosteum secrete osteoid onto surface of Cartilage = Bone Collar
2. Cartilage in Center of Diaphysis Calcifies and Develops Cavities
Chondrocytes Hypertrophy
Matrix Calcifies
Chondrocytes die
Matrix deteriorates forming cavities
3. The Periosteal Bud invades the Internal Cavities & Spongy Bone forms = Primary Ossification Center
Periosteal Bud = Nutrient Artery & Vein, Lymphatic Vessel, nerve, osteoblasts & osteoclasts
Osteoclasts erode calcified matrix; Osteoblasts secret osteoid on matrix fragments = Early Spongy Bone

23. 4. Diaphysis Elongates & Medullary Cavity forms
Osteoclasts degrade Spongy Bone to make Medullary Cavity
Secondary Ossification Centers appear in epiphyses via same process as Primary Ossification Centers (Chondrocytes hypertrophy, calcifiy, & die, Matrix deteriorates, Periosteal Bud, Osteoclasts remove matrix & Osteoblasts secrete osteoid)
The mostly Cartilage Epiphysis is rapidly growing
2nd Ossification Center grows as adjacent Cartilage is calcified and erodes
Birth
Epiphyseal
blood vessel
Medullary
cavity

24. D. Postnatal Growth 5. The Epiphyses Ossify Epiphyses Ossify
Cartilage remains only in the epiphyseal plates
Cartilage at ends as Articular Cartilage
Postnatal Growth
D. Postnatal Growth
Bone ossification approached the epiphyseal Plates
Epiphyseal Plates continues to grow
Appositional and Interstitial Growth
3. MICROSCOPIC VIEW– 5 Zones in Long Bone Growth
Slide 5
Articular
cartilage
Spongy
bone
Epiphyseal
plate
cartilage
Childhood to
Adolescence to Adulthood
© 2013 Pearson Education, Inc.

25. D-3 Microscopic View-- 5 Zones in Long Bone Growth
a) Resting zone (Reserve)
a) Zone of Proliferation (Growth zone)
- cartilage cells
b) Hypertrophic zone
c) Calcification Zone (Zone of Erosion, destruction)
- the matrix becomes:
d) Ossification Zone (Zone of Bone Formation)

26. 4. Adulthood: Ossification Ends Skeleton: is fully formed
D. Postnatal Growth …
4. Adulthood: Ossification Ends
Skeleton: is fully formed
Cartilage in 2 places
Epiphyseal Line:
Growth Finished
WIDTH GROWTH
5. Growth in Width & Modeling (Remodeling)
- Modeling: occurs during a bone’s growth
a) Appositional Growth--in diameter:
b) Osteoclasts of Endosteum
c) Proportions:
Shape before Appositional Growth 3. 1. 2.

27. Figure 6.11 Long bone growth and remodeling during youth.
Bone growth--width
Bone Modeling
Bone growth--Length
Articular cartilage
Cartilage
grows here.
Bone
replaces cartilage
here.
Epiphyseal plate
2. Bone that was
here has been
resorbed.
Cartilage
grows here.
1. Appositional
growth adds
bone here.
Bone replaces
cartilage here.
3. Bone that was
here has been
resorbed.
© 2013 Pearson Education, Inc.

28. END Continue to PPT #2

29. Review Question
3. Impact resistance is provided by _________ bone while the mass of a bone is lightened by ____________ bone without jeopardizing strength. Bone, in general, helps to store ___________and fat.
Compact …. Spongy …... Minerals

30. Review Question
4. Bones are covered with a layer of dens connective tissue known as the _____________ and is 65% ______________________. Bone cells include stem cells known as ______________, bone makers called ____________, and bone breakers called ____________.
periosteum
hydroxyapatites
osteogenic cells
osteoblasts
osteoclasts

31. Participating…
5. Blood vessels deliver nutrients to bone through long ___________ canals running through the middle of each osteon and sideways _____________ canals. Bone cells trapped inside lacunae receive nourishment via ______________ that radiate from the central canal and __________ fibers provide resistance to stress due to their arrangement within _____________
central
perforating
canaliculi
collagen
lamellae

32. Review Questions
6. Intermembranous ossification forms the clavicles and most _______ bones of the skull. Endochondral ossification occurs when hyaline ___________ is replaced by bone. __________ ossification centers typically become ___________ cavities in long bones, but secondary ossification centers remain what type of bone?
flat
cartilage
Primary
medullary
spongy
Hyaline
cartilage
Epiphyseal
blood vessel
plate
Medullary
cavity
Articular
Bone collar 1 2 3 4 5

33. Cartilage Perichondrium: Tissue Functions resists outward expansion
forms new chondrocytes,
feeds cartilage
Three types– REVIEW
STUDENTS DO

34. Growth of Cartilage Not in Mature Cartilage Types:
Appositional – from perichondrium
Interstitial – inside cartilage
Epiphysial Plate:

35. Bone Structure … Chemical Composition of Bone
Organic
Cells
Ground Substance
Proteoglycans & glycoproteins
Collagen Fibers
Osteoid = newly secreted Ground &
Collagen
Inorganic
Ca-Phosphate = hydroxyapatites = 65%

36. Figure 6.8 Endochondral ossification in a long bone.
Slide 2
Week 9
Hyaline
cartilage
Bone collar
Primary
ossification
center
Bone collar forms around the
diaphysis of the hyaline cartilage
model. 1
© 2013 Pearson Education, Inc.

37. Figure 6.8 Endochondral ossification in a long bone.
Slide 3
Area of deteriorating
cartilage matrix
Chondrocytes in shaft Hypertrophy
In middle:
Cartilage matrix calcifies
Chondrocytes die
Calcified matrix deteriorates
Rest of cartilage alive and mitotic
Cartilage in the center
of the diaphysis calcifies
and then develops cavities. 2
© 2013 Pearson Education, Inc.