muscle contraction. microscopic anatomy of skeletal muscle sarcomere contractile unit of a muscle...
TRANSCRIPT
MUSCLE CONTRACTION
Microscopic Anatomy of Skeletal Muscle
• Sarcomere• Contractile unit of a muscle fiber
Figure 6.3b
Microscopic Anatomy of Skeletal Muscle• Sarcomere• Thick filaments = myosin• Thin filaments = actin
Figure 6.3c
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 1) Sarcoplasmic reticulum releases Ca2+
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 2) Ca2+ causes myosin (thick) heads to attach to actin (thin)
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 2) Ca2+ causes myosin (thick) heads to attach to actin (thin)
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 3) ATP gives myosin power to “pull” actin along it
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 3) ATP gives myosin power to “pull” actin along it
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 4) Myosin heads bind to the next site along actin (thin)
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 4) Myosin heads bind to the next site along actin (thin)
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 5) Continued action causes actin to continue to slide along myosin
Figure 6.7
The Sliding Filament Theory of Muscle Contraction (5 Steps)
• 5) Continued action causes actin to continue to slide along myosin
Figure 6.7
Muscle Video• http://www.youtube.com/watch?v=NRzJjx3ANuE
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