Question

Assertion : Myasthenia gravis is an autoimmune disease.

Reason : Immune system rejects the transplant muscles.

• A. Both the Assertion and the Reason are true and the Reason is a correct explanation of the Assertion.
• B. Both the Assertion and Reason are true but the Reason is not a correct explanation of the Assertion.
• C. The Assertion is true but the Reason is false.
• D. Both the Assertion and Reason is false.
• E. The Assertion is false but Reason is true.

Answer 1

Answer: (C)

The Assertion is true but the Reason is false.

Myasthenia gravis is caused by a defect in the transmission of nerve impulses to muscles. It occurs when normal communication between the nerve and muscle is interrupted at the neuromuscular junction (the place where nerve cells connect with the muscles they control) because, antibodies block, alter or destroy the receptors for acetylcholine at the neuromuscular junction, which prevents the muscle contraction from occurring. These antibodies are produced by the body's own immune system and thus, called as autoimmune disease.

Hence, the correct answer is option C.