Skeletal muscle contraction through flow chart
Understand the Problem
The question is asking for a flow chart that explains the process of skeletal muscle contraction, which involves the sequence of physiological events that lead to contraction at the muscle fibers level.
Answer
Brain sends signal, acetylcholine release, action potential, calcium release, cross-bridge cycling, contraction, relaxation.
The final answer is as follows: 1. Brain sends a signal. 2. Signal travels via motor neurons to neuromuscular junction. 3. Acetylcholine is released and binds to receptors on muscle fiber. 4. Action potential travels along sarcolemma and T-tubules. 5. Calcium ions are released from the sarcoplasmic reticulum. 6. Calcium binds to troponin, revealing binding sites on actin. 7. Myosin heads bind to actin forming cross-bridges. 8. ATP is hydrolyzed causing myosin heads to pull actin filaments (power stroke). 9. Muscle contracts. 10. Calcium is pumped back into the sarcoplasmic reticulum, leading to muscle relaxation.
Answer for screen readers
The final answer is as follows: 1. Brain sends a signal. 2. Signal travels via motor neurons to neuromuscular junction. 3. Acetylcholine is released and binds to receptors on muscle fiber. 4. Action potential travels along sarcolemma and T-tubules. 5. Calcium ions are released from the sarcoplasmic reticulum. 6. Calcium binds to troponin, revealing binding sites on actin. 7. Myosin heads bind to actin forming cross-bridges. 8. ATP is hydrolyzed causing myosin heads to pull actin filaments (power stroke). 9. Muscle contracts. 10. Calcium is pumped back into the sarcoplasmic reticulum, leading to muscle relaxation.
More Information
This explanation summarizes the physiological process of skeletal muscle contraction and relaxation based on the sliding filament theory.
Tips
A common mistake is forgetting the role of calcium ions in the process.
Sources
- Muscle Fiber Contraction and Relaxation | Anatomy and Physiology I - courses.lumenlearning.com
- The Sliding Filament Theory of Muscle Contraction - Nature - nature.com
