Chondroblast Chondrocyte (Lacunae) Firm ground … · Chondroblast ‐> Chondrocyte (Lacunae) Firm ground ... Education, Inc. Figure 6.7 Microscopic anatomy of ... 2010 Pearson Education,

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Figure 4.8g Connective tissues.

(g) Cartilage: hyaline

Description: Amorphous but firmmatrix; collagen fibers form animperceptible network; chondroblastsproduce the matrix and when mature(chondrocytes) lie in lacunae.

Function: Supports and reinforces;has resilient cushioning properties;resists compressive stress.

Location: Forms most of theembryonic skeleton; covers the endsof long bones in joint cavities; formscostal cartilages of the ribs; cartilagesof the nose, trachea, and larynx.

Photomicrograph: Hyaline cartilage from thetrachea (750x).

Costalcartilages

Chondrocytein lacuna

Matrix

Pg 131

Chondroblast ‐> Chondrocyte (Lacunae)Firm ground substance (chondroitin sulfate and water)Collagenous and elastic fibersNo BV or nervesPerichondrium (dense irregular)

Thickness?Metabolism?


Figure 6.1 The bones and cartilages of the human skeleton.

Axial skeleton

Appendicular skeleton

Hyaline cartilages

Elastic cartilages

Fibrocartilages

Cartilages

Bones of skeleton

EpiglottisLarynx

TracheaCricoidcartilage Lung

Respiratory tube cartilagesin neck and thorax

ThyroidcartilageCartilage in

external earCartilages innose

ArticularCartilageof a joint

Costalcartilage

Cartilage inIntervertebraldisc

Pubicsymphysis

Articular cartilageof a joint

Meniscus (padlikecartilage inknee joint)

Pg 174

SupportSmooth

surfaceCushions


Figure 4.8g Connective tissues.

(g) Cartilage: hyaline

Description: Amorphous but firmmatrix; collagen fibers form animperceptible network; chondroblastsproduce the matrix and when mature(chondrocytes) lie in lacunae.

Function: Supports and reinforces;has resilient cushioning properties;resists compressive stress.

Location: Forms most of theembryonic skeleton; covers the endsof long bones in joint cavities; formscostal cartilages of the ribs; cartilagesof the nose, trachea, and larynx.

Photomicrograph: Hyaline cartilage from thetrachea (750x).

Costalcartilages


Matrixglassy

Pg 131


Figure 4.8h Connective tissues.

(h) Cartilage: elastic

Description: Similar to hyalinecartilage, but more elastic fibersin matrix.

Function: Maintains the shapeof a structure while allowinggreat flexibility.

Location: Supports the externalear (pinna); epiglottis.

Photomicrograph: Elastic cartilage fromthe human ear pinna; forms the flexibleskeleton of the ear (800x).


Matrix

Pg 132


Figure 4.8i Connective tissues.

(i) Cartilage: fibrocartilage

Description: Matrix similar tobut less firm than that in hyalinecartilage; thick collagen fiberspredominate.

Function: Tensile strengthwith the ability to absorbcompressive shock.

Location: Intervertebral discs;pubic symphysis; discs of kneejoint.

Photomicrograph: Fibrocartilage of anintervertebral disc (125x). Special stainingproduced the blue color seen.

Intervertebraldiscs

Chondrocytesin lacunae

Collagenfiber

Pg 132

Tough!Forms discs and pads


Figure 6.7 Microscopic anatomy of compact bone.

Endosteum lining bony canalsand covering trabeculae

Perforating (Volkmann’s) canal

Perforating (Sharpey’s) fibers

Periosteal blood vesselPeriosteum

Lacuna (withosteocyte)

(a)

(b) (c)

Lacunae

Lamellae

NerveVeinArtery

CanaliculiOsteocytein a lacuna

Circumferentiallamellae

Osteon(Haversian system)

Central(Haversian) canal

Centralcanal

Interstitial lamellae

Lamellae

Compactbone

Spongy bone

Pg 181

SupportProtectionBlood formationStorehouseMovement

Hydroxyapatite(calcium salts)

Bone Cells‐osteoblast‐osteocyte‐osteoclast

Periosteum(dense irr.)

2 types of bone

osteoblast

Osteoblasts & clasts


Proximalepiphysis

(b)

(c)(a)

Yellowbone marrow

Endosteum

Epiphysealline

Articularcartilage

Periosteum

Spongy bone

Compact boneMedullarycavity (linedby endosteum)

Compact bone

Compact bone

Periosteum

Perforating(Sharpey’s)fibersNutrientarteries

Diaphysis

Distalepiphysis

Figure 6.3 The structure of a long bone (humerus of arm).

Pg 176

Spongy = Cancellous

Spaces contain marrowTrabeculae

‐Ends of long bones‐Shaft of young bones‐In flat, short and irregular bones


Figure 6.7 Microscopic anatomy of compact bone.

Endosteum lining bony canalsand covering trabeculae

Perforating (Volkmann’s) canal

Perforating (Sharpey’s) fibers

Periosteal blood vesselPeriosteum

Lacuna (withosteocyte)

(a)

(b) (c)

Lacunae

Lamellae

NerveVeinArtery

CanaliculiOsteocytein a lacuna

Circumferentiallamellae

Osteon(Haversian system)

Central(Haversian) canal

Centralcanal

Interstitial lamellae

Lamellae

Compactbone

Spongy bone

Pg 181

Compact forms shaft of long bones and a shell over spongy bone


Figure 4.8j Connective tissues.

(j) Others: bone (osseous tissue)

Description: Hard, calcifiedmatrix containing many collagenfibers; osteocytes lie in lacunae.Very well vascularized.

Function: Bone supports andprotects (by enclosing);provides levers for the musclesto act on; stores calcium andother minerals and fat; marrowinside bones is the site for bloodcell formation (hematopoiesis).

Location: Bones

Photomicrograph: Cross‐sectional viewof bone (125x).

Lacunae

Lamella

Centralcanal

Pg 133


Figure 6.2 Classification of bones on the basis of shape.

(a) Long bone(humerus)

(b) Irregular bone(vertebra), rightlateral view

(d) Short bone(talus)

(c) Flat bone(sternum)

Pg 175


Figure 6.3a The structure of a long bone (humerus of arm).

Proximal epiphysis

(a)

Epiphyseal line (plate)

Articularcartilage

Periosteum

Spongy bone

Compact boneMedullarycavity (linedby endosteum with clasts & blasts)Diaphysis

Distal epiphysis

Pg 176

Red-> Yellow

Formation of bony skeleton

Intramembranous: skull bones, mandible, part of clavicle

Endochondral: Most bones of the body

Bone is only deposited in an area with less highly specialized connective tissue.

Intramembranousmesenchyme ‐> Dense Irr. ‐> Spongy ‐> Compact

C.T. Bone Bone(inside)


Figure 6.5 Flat bones consist of a layer of spongy bone sandwiched between two thin layers of compact bone.

Compactbone

Trabeculae

Spongy bone(diploë)

Layers?

Pg 179

Bone is only deposited in an area with less highly specialized connective tissue.

Intramembranousmesenchyme ‐> Dense Irr. ‐> Spongy ‐> Compact

C.T. Bone Bone(inside)

Endochondralmesenchyme ‐> Hyaline ‐> Spongy ‐> Compact

Cartilage Bone Bone


Figure 6.9 Endochondral ossification in a long bone.

1 2 3 4 5Bone collarforms aroundhyaline cartilagemodel.

Cartilage in thecenter of thediaphysis calcifiesand then developscavities.

The periostealbud invades theinternal cavitiesand spongy bonebegins to form.

The diaphysis elongatesand a medullary cavityforms as ossificationcontinues. Secondaryossification centers appearin the epiphyses inpreparation for stage 5.

The epiphysesossify. Whencompleted, hyalinecartilage remains onlyin the epiphysealplates and articularcartilages.

Hyalinecartilage

Area ofdeterioratingcartilage matrix

Epiphysealblood vessel

Spongyboneformation

Epiphysealplatecartilage

Secondaryossificationcenter

Bloodvessel ofperiostealbud

Medullarycavity

Articularcartilage

Childhood toadolescence

BirthWeek 9 Month 3

Spongybone

Bonecollar Primaryossificationcenter

Pg 183


Figure 6.11 Long bone growth and remodeling during youth.

Bone growth Bone remodeling

Articular cartilage

Epiphyseal plate

Cartilagegrows here.

Cartilageis replacedby bone here.

Cartilagegrows here.

Bone isresorbed here.

Bone isresorbed here.

Bone is addedby appositionalgrowth here. Cartilage

is replacedby bone here.

Pg 185

In Length: Until end of puberty

Endochondral

In Width (appositional): occurs throughout life

IntramembranousAchondroplasia

GiantismAcromegalyPituitary Dwarfism


Figure 16.11a The parathyroid glands.

Pharynx (posterioraspect)

Thyroid glandCalcitonin

Parathyroid glandsPTH

Trachea

Esophagus

(a)Pg 613

PTH-Low Blood Calcium-Stimulates Osteoclasts, Kidneys

Calcitonin-High Blood Calcium-Stimulates Osteoblasts, Kidneys

Osteoporosis

Estrogen‐Reduced with menopause‐Loss of bone massCalciumVitamin DExercise


Figure 6.16 The contrasting architecture of normal versus osteporotic bone.

Pg 191

fibrous


Figure 6.15 Stages in the healing of a bone fracture.

Hematoma Externalcallus

Bonycallus ofspongybone

Healedfracture

Newbloodvessels

Spongybonetrabecula

Internalcallus(fibroustissue andcartilage)

1 A hematoma forms. 2 Fibrocartilaginouscallus forms.

3 Bony callus forms. 4 Boneremodelingoccurs.

Pg 189

Intramembranous & EndochondralOsteoclasts & Osteoblasts

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Chondroblast Chondrocyte (Lacunae) Firm ground … · Chondroblast ‐> Chondrocyte (Lacunae) Firm ground ... Education, Inc. Figure 6.7 Microscopic anatomy of ... 2010 Pearson Education,