Ch06 a.bone

Human
Anatomy
& Physiology
SEVENTH EDITION
Elaine N. Marieb
Katja Hoehn
Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings
PowerPoint® Lecture Slides
prepared by Vince Austin,
Bluegrass Technical
and Community College
C H A P T E R 6Bones and
Skeletal
Tissues
P A R T A

Skeletal Cartilage
 Contains no blood vessels or nerves
 Surrounded by the perichondrium (dense irregular
connective tissue) that resists outward expansion
 Three types – hyaline, elastic, and fibrocartilage

Hyaline Cartilage
 Provides support, flexibility, and resilience
 Is the most abundant skeletal cartilage
 Is present in these cartilages:
 Articular – covers the ends of long bones
 Costal – connects the ribs to the sternum
 Respiratory – makes up larynx, reinforces air
passages
 Nasal – supports the nose

Elastic Cartilage
 Similar to hyaline cartilage, but contains elastic
fibers
 Found in the external ear and the epiglottis

Fibrocartilage
 Highly compressed with great tensile strength
 Contains collagen fibers
 Found in menisci of the knee and in intervertebral
discs

Growth of Cartilage
 Appositional – cells in the perichondrium secrete
matrix against the external face of existing
cartilage
 Interstitial – lacunae-bound chondrocytes inside
the cartilage divide and secrete new matrix,
expanding the cartilage from within
 Calcification of cartilage occurs
 During normal bone growth
 During old age

Bones and Cartilages of the Human Body
Figure 6.1

Classification of Bones
 Axial skeleton – bones of the skull, vertebral
column, and rib cage
 Appendicular skeleton – bones of the upper and
lower limbs, shoulder, and hip

Classification of Bones: By Shape
 Long bones –
longer than
they are wide
(e.g., humerus)
Figure 6.2a

 Short bones
 Cube-shaped
bones of the
wrist and
ankle
 Bones that
form within
tendons (e.g.,
patella)
Figure 6.2b

 Flat bones –
thin, flattened,
and a bit
curved (e.g.,
sternum, and
most skull
bones)
Figure 6.2c

 Irregular
bones –
bones with
complicated
shapes (e.g.,
vertebrae and
hip bones)
Figure 6.2d

Function of Bones
 Support – form the framework that supports the
body and cradles soft organs
 Protection – provide a protective case for the brain,
spinal cord, and vital organs
 Movement – provide levers for muscles

Function of Bones
 Mineral storage – reservoir for minerals, especially
calcium and phosphorus
 Blood cell formation – hematopoiesis occurs
within the marrow cavities of bones

Bone Markings
 Bulges, depressions, and holes that serve as:
 Sites of attachment for muscles, ligaments, and
tendons
 Joint surfaces
 Conduits for blood vessels and nerves

Bone Markings: Projections –
Sites of Muscle and Ligament Attachment
 Tuberosity – rounded projection
 Crest – narrow, prominent ridge of bone
 Trochanter – large, blunt, irregular surface
 Line – narrow ridge of bone

Sites of Muscle and Ligament Attachment
 Tubercle – small rounded projection
 Epicondyle – raised area above a condyle
 Spine – sharp, slender projection
 Process – any bony prominence

Projections That Help to Form Joints
 Head – bony expansion carried on a narrow neck
 Facet – smooth, nearly flat articular surface
 Condyle – rounded articular projection
 Ramus – armlike bar of bone

Bone Markings: Depressions and Openings
 Meatus – canal-like passageway
 Sinus – cavity within a bone
 Fossa – shallow, basin-like depression
 Groove – furrow
 Fissure – narrow, slit-like opening
 Foramen – round or oval opening through a bone

Gross Anatomy of Bones: Bone Textures
 Compact bone – dense outer layer
 Spongy bone – honeycomb of trabeculae filled
with yellow bone marrow

Bone Markings
Table 6.1

Structure of Long Bone
 Long bones consist of a diaphysis and an epiphysis
 Diaphysis
 Tubular shaft that forms the axis of long bones
 Composed of compact bone that surrounds the
medullary cavity
 Yellow bone marrow (fat) is contained in the
medullary cavity

 Epiphyses
 Expanded ends of long bones
 Exterior is compact bone, and the interior is
spongy bone
 Joint surface is covered with articular (hyaline)
cartilage
 Epiphyseal line separates the diaphysis from the
epiphyses

Figure 6.3

Figure 6.3a

Figure 6.3b

Figure 6.3c

Bone Membranes
 Periosteum – double-layered protective membrane
 Outer fibrous layer is dense regular connective
tissue
 Inner osteogenic layer is composed of osteoblasts
and osteoclasts
 Richly supplied with nerve fibers, blood, and
lymphatic vessels, which enter the bone via
nutrient foramina
 Secured to underlying bone by Sharpey’s fibers

Bone Membranes
 Endosteum – delicate membrane covering internal
surfaces of bone

Structure of Short, Irregular, and Flat Bones
 Thin plates of periosteum-covered compact bone
on the outside with endosteum-covered spongy
bone (diploë) on the inside
 Have no diaphysis or epiphyses
 Contain bone marrow between the trabeculae

Structure of a Flat Bone
Figure 6.4

Location of Hematopoietic Tissue
(Red Marrow)
 In infants
 Found in the medullary cavity and all areas of
spongy bone
 In adults
 Found in the diploë of flat bones, and the head of
the femur and humerus

Microscopic Structure of Bone:
Compact Bone
 Haversian system, or osteon – the structural unit of
compact bone
 Lamella – weight-bearing, column-like matrix
tubes composed mainly of collagen
 Haversian, or central canal – central channel
containing blood vessels and nerves
 Volkmann’s canals – channels lying at right angles
to the central canal, connecting blood and nerve
supply of the periosteum to that of the Haversian
canal

Microscopic Structure of Bone:
Compact Bone
 Osteocytes – mature bone cells
 Lacunae – small cavities in bone that contain
osteocytes
 Canaliculi – hairlike canals that connect lacunae to
each other and the central canal

Microscopic Structure of Bone: Compact
Bone
Figure 6.6a, b

Bone
Figure 6.6a

Bone
Figure 6.6b

Bone
Figure 6.6c

Chemical Composition of Bone: Organic
 Osteoblasts – bone-forming cells
 Osteocytes – mature bone cells
 Osteoclasts – large cells that resorb or break down
bone matrix
 Osteoid – unmineralized bone matrix composed of
proteoglycans, glycoproteins, and collagen

Chemical Composition of Bone: Inorganic
 Hydroxyapatites, or mineral salts
 Sixty-five percent of bone by mass
 Mainly calcium phosphates
 Responsible for bone hardness and its resistance to
compression

 Hydroxylapatite, also called hydroxyapatite
(HA), is a naturally occurring mineral form of
calcium apatite with the formula Ca5(PO4)3(OH),
but is usually written Ca10(PO4)6(OH)2 to denote that
the crystal unit cell comprises two entities.
Hydroxylapatite is the hydroxyl endmember of the
complex apatite group. The OH- ion can be
replaced by fluoride, chloride or carbonate,
producing fluorapatite or chlorapatite. fluorosis.

Bone Development
 Osteogenesis and ossification – the process of bone
tissue formation, which leads to:
 The formation of the bony skeleton in embryos
 Bone growth until early adulthood
 Bone thickness, remodeling, and repair

Formation of the Bony Skeleton
 Begins at week 8 of embryo development
 Intramembranous ossification – bone develops
from a fibrous membrane
 Endochondral ossification – bone forms by
replacing hyaline cartilage

Intramembranous Ossification
 Formation of most of the flat bones of the skull and
the clavicles
 Fibrous connective tissue membranes are formed
by mesenchymal cells

Ch06 a.bone

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Ch06 a.bone

Similar to Ch06 a.bone (20)

More from TheSlaps

More from TheSlaps (20)

Ch06 a.bone