A&P Chapter 6

6
Bones and Skeletal

• Human skeleton is initially made up of cartilages and fibrous membranes as early supports – These are replaced by bone as we grow
– The cartilages found in adults are in places where flexible skeletal tissue is needed

Skeletal Cartilages
• Contain no _______ ________ or ______, and consist mainly of water
• Dense irregular connective tissue girdle of perichondrium (around the cartilage) contains blood vessels for nutrient delivery to cartilage
– Nutrients diffuse through the matrix to reach the cartilage cells

Skeletal Cartilages
1. Hyaline cartilages
– Provide: support, flexibility, and resilience
– Most abundant type
– 1. Articular cartilages- covers the ends of bones and moveable joints
– 2. Costal cartilages
– 3. Respiratory cartilages- form the skeleton of the larynx – 4. Nasal cartilages

Skeletal Cartilages
2. Elastic cartilages
– Similar to hyaline cartilages, but contain
________ fibers

3. Fibrocartilages
– ___________ fibers—have great tensile strength
– Menisci, discs between the vertebrae

Cartilage in external ear

Cartilage in
Intervertebral
disc

Cartilages in nose Articular
Cartilage
of a joint

Epiglottis
Thyroid
cartilage
Cricoid
cartilage

Larynx
Trachea
Lung

Costal cartilage Respiratory tube cartilages in neck and thorax
Pubic
symphysis
Meniscus
(padlike cartilage in knee joint)
Articular
cartilage of a joint

Bones of skeleton
Axial skeleton
Appendicular skeleton

Cartilages
Hyaline cartilages
Elastic cartilages
Fibrocartilages
Figure 6.1

Growth of Cartilage
• Appositional
– Cells secrete matrix against the external face of existing cartilage • Interstitial
– Chondrocytes divide and secrete new matrix, expanding cartilage from within

• Calcification of cartilage occurs during
– Normal bone growth
– Old age

Bones of the Skeleton
• Two main groups, by location
– Axial skeleton (brown)
– Appendicular