Which of the following is a disorder of the muscular/skeletal system?

Choose the correct pair.

Write a few lines about Gout.

Muscular dystrophy in humans is a

In Myasthenia gravis . . . . . . is affected.

Which of the following is an incorrect statement about myasthenia gravis?
$(I)$ It is not an autoimmune disorder.
$(II)$ It affects the neuromuscular junction.
$(III)$ It occurs due to low $Ca^{++}$ in body fluid.
$(IV)$ Paralysis of skeletal muscle is a symptom of myasthenia gravis.