1. All or None Principal, Fatigue, Tetany, and Muscular Contractions By Alexandra Shafi All or None Principal, Fatigue, Tetany, Muscular Contraction By Alexandra Shafi

2. All or None Principal based on the fact that the strength of an electrical event or stimulus on a nerve or a muscle fiber will not affect the strength of the response of the nerve or muscle fiber, as long as the stimulus is above the threshold level to create the response.

3. In order to contract the cell must… Have end plate with channels that open or close to let sodium flow through depolarize above the threshold value If stimulus is any strength above threshold, muscle fiber complete contraction response if stimulus is not great enough is no response at all.

4. Fatigue Fatigue is a feeling of weakness, tiredness, or lack of energy Other symptoms include Pain Emotionally drained Lack of interest

5. Causes of Fatigue Over exertion in physical activity StressAnemia Chronic Lung diseases Combat fatigue In order to cure must treat underlying cause

6. combination of signs and symptoms, due usually to low calcium (hypocalceamia) Muscle Spasms in face hand, or foot Overactive neurological reflexes Abnormal sensations Tingling lips Burning lips Burning tongue General muscle aches

7. Tetany is not always recognized by doctors Can be caused from Kidney disease Vitamin D Deficiency Can be treated with Calcium Gluconate CalfortCal-G

8. Muscle Contractions To make a muscle fiber contract, brain sends To make a muscle fiber contract, brain sends a signal to a motor neuron at the neuromuscular junction. at the neuromuscular junction. Releases neurotransmitter, called acetylcholine Acetylcholine binds to receptors Acetylcholine binds to receptors on calcium channels The calcium binds to the troponin C present on the actin (coated with ADP) Actin moves towards myosin(coated with ATP

9. Muscle Contraction Cont helps depolarize the muscle fibers helps depolarize the muscle fibers ATP helps z fibers to contract which are part of the sarcomere Z fibers move toward I band and causes contraction