Answer to Question 1
Myasthenia gravis is a neuromuscular disease. Neurologists propose that the client has an autoimmune disorder that affects the neuromuscular junction, which is the point of contact between a muscle fiber and the nerve innervating it. Thus the client has an immune response to the neurotransmitter receptor of the neuromuscular junction. In addition, the client builds antibodies that block receptors. Blocked receptors cannot respond to neurotransmitters. Therefore, as myasthenia gravis progresses, more and more receptors are blocked, and fewer and fewer ion channels can be activated to depolarize neurons. Remember that ions are particles that carry a negative or positive charge.
One important characteristic of myasthenia gravis is extreme fatigue, especially starting around noon and progressing throughout the rest of the day. The speech-language therapist pathologist is frequently the first person to make a tentative diagnosis of myasthenia gravis. Usually the client tells the therapist or pathologist that it is becoming increasingly difficult to speak and to be understood by other individuals. Thus difficulty speaking is usually an early symptom of myasthenia gravis, along with an inability to clearly express him- or herself.
Answer to Question 2
premotor
A phylogenetic tree showing the major eukaryotic supergroups.
The major types of plant nutrients and their sources.
Major Arteries
Major fluid compartments in the body
Major “identity elements” in some tRNAs
Major Somatic Motor Tracts and Pathways