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:::::'''Fig. 2.10 Collagen cross-links'''
:::::'''Fig. 2.10 Collagen cross-links'''
:::::Crosslinks in immature connective tissue pass between collagen molecules within a fibril (a). The molecules are linked head to tail to form an infinite polymer.
:::::Crosslinks in immature connective tissue pass between collagen molecules within a fibril (a). The molecules are linked head to tail to form an infinite polymer.
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::::In a mature collagen fibre, (b), the crosslinks pass between the fibrils to link them in register.
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:::::In a mature collagen fibre, (b), the crosslinks pass between the fibrils to link them in register.
:::::(Adapted from Bailey, 1988).
:::::(Adapted from Bailey, 1988).
[[File:QMSection2.11.png|thumb|'''Fig. 11 Tensile stress in collagen''']]
[[File:QMSection2.11.png|thumb|'''Fig. 11 Tensile stress in collagen''']]
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::::'''Fig. 11 Tensile stress in collagen'''
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:::::'''Fig. 11 Tensile stress in collagen'''
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::::The stress–strain relationship in a bundle of collagen fibres, at a low rate of strain.
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:::::The stress–strain relationship in a bundle of collagen fibres, at a low rate of strain.
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::::Phase I: Rapid elongation as the "crimp" in the collagen fibres is eliminated. This part of the curve is smaller at the high strain rates likely to occur in vivo.
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:::::Phase I: Rapid elongation as the "crimp" in the collagen fibres is eliminated. This part of the curve is smaller at the high strain rates likely to occur in vivo.
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::::Phase II: Stress is proportional to strain. This elastic phase of collagen is the phase most useful in vivo.
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:::::Phase II: Stress is proportional to strain. This elastic phase of collagen is the phase most useful in vivo.
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::::Phase III: Breakdown of the crystalline components of the collagen fibres. Deformation takes place with progressively less stress.
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:::::Phase III: Breakdown of the crystalline components of the collagen fibres. Deformation takes place with progressively less stress.