I took the test that featured this question the answer is A
The Hawaiian islands were formed by hot spots. Hot spots are areas deep in the mantle where magma rises in cracks and fissures. The tectonic plate moves over the hot spot, which eventually cools to form the island.
True, there is a deficiency of the enzyme.
Answer:
The correct answer is ''loss of acetylcholine receptors in the end-plate membrane.''
Explanation:
Myasthenia gravis represents a human autoimmune disease. The neuromuscular junction abnormalities that occur in this disease are due to antibody-mediated processes. A reduction in the number of functional acetylcholine receptors on the postsynaptic membrane was established to contribute to the physiological abnormalities of myasthenia gravis. The reduction in receptors is due to immunological alterations directed against the acetylcholine receptor. Normally, when acetylcholine binds to its receptor, it opens allowing the rapid entry of cations, especially sodium. With this, the depolarization of the postsynaptic region of the muscle fiber occurs. Although acetylcholine is normally released in myasthenia gravis, it is not capable of causing an action potential in the muscle sufficient to initiate or weaken contraction. In patients with myasthenia gravis, failure to activate muscles is responsible for myasthenic fatigue. Most patients have elevated serum titers of antireceptor antibodies, which in turn accelerate receptor degradation.
Each box weighs the same but the bottom left truck has more boxes then the rest so it has more mass therefore more gravity acting on it.
