Final answer:
Myasthenia gravis is a genetic neuromuscular disorder that causes muscle weakness and fatigue. McArdle disease is characterized by progressive muscle weakness caused by a build-up of glycogen. Muscle fatigue occurs when a muscle can no longer contract in response to signals from the nervous system.
Step-by-step explanation:
Myasthenia gravis is a genetic neuromuscular disorder characterized by fluctuating muscle weakness and fatigue. The condition is caused by the immune system blocking acetylcholine receptors on muscle cells, which impairs muscle contraction.
One of the features of McArdle disease, also known as glycogen storage disease type II, is muscle weakness. McArdle disease is caused by a build-up of glycogen, a form of stored glucose, which leads to progressive muscle weakness throughout the body.
Muscle fatigue is a term used to describe when a muscle can no longer contract in response to signals from the nervous system. It can be caused by factors such as depleted ATP levels, lactic acid buildup, imbalances in ion levels, and damage to the muscle membranes.