Transcript Muscles & Bones - Parma City School District

Muscles & Bones
Axial vs. Appendicular
• Axial Skeleton: Skull, Vertebral Column
• Appendicular: Pectoral and Pelvic Girdles
Muscles
• Muscles are attached to bones by tendons
• Skeletal movement is caused by muscle
contraction and relaxation (Pull not push)
• Origin: attached to the stationary bone
• Insertion: attached to the bone that moves
• Flexor: pulls bone towards body
• Extensor: extends bone away from body
Muscle Twitch Contraction
• Latent Period = period of time between
stimulation and initiation of contraction
• Contraction Period: Muscle contracts
• Relaxation Period: Muscle Relaxes
• Summation: Muscle remains contracted
after multiple stimuli without relaxing
• Tetanus: muscle fatigue due to depletion of
energy
• Fatigue: muscle remains relaxed even
though stimulation continues