Sliding filaments

• The myosin myofilament consists of thousands of myosin heads
• Myosin heads attach to the actin myofilaments pulling it across the myosin myofilament
• results in a decrease in the length of the sacromeres, a decrease in the length of the I band and a decrease in the distance of the H-zone
• 1. the myosin head attached to the actin which is binded to ADP and Pi
• 2. The phosphate group is released causing the myosin head to bend and pull along the actin filament. so the actin slides along towards the M line
• 3. ADP is released and combines with the phosphate group producing ATP
• 4. ATP attaches to the myosin head causing the link between the myosin and actin to weaken so the myosin head detaches
• 5. The ATP splits into ADP and Pi causing the myosin head to become energized so become straight again
• diagram

  A) I band

  B) A band

  C) myosin myofilament

  D) actin myofilament

  E) z line

  F) h-zone

  G) z line

  H) myosin heads