Nokea
The 'synaptic cleft' of a neuromuscular junction is
- A. a groove in the muscle cell plasma membrane through which neurons grow
- B. that portion of the cell surface receptor molecule on the surface of a muscle cell, into which the ligand binds
- C. a depression at the end of an axon from which neurotransmitters are secreted
- D. the space between the plasma membrane of a neuron on the pre-synaptic side of the synapse, and the plasma membrane of the muscle cell on the post-synaptic side of the synapse
Correct Answer: D
Rationale: The synaptic cleft is the narrow space between the presynaptic neuron and the postsynaptic muscle cell. It is where neurotransmitters are released and diffuse to bind receptors on the muscle cell, initiating muscle contraction. This structure is essential for signal transmission at the neuromuscular junction.
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One criterion identified by the American College of Rheumatology for a diagnosis of fibromyalgia is
- A. Fiber atrophy found on muscle biopsy
- B. Elimination of all other causes of musculoskeletal pain
- C. The presence of the manifestations of chronic fatigue syndrome
- D. The elicitation of pain on palpation of at least 11 of 18 identified tender points
Correct Answer: D
Rationale: Tender points are diagnostic for fibromyalgia.
A 58-year-old female, accompanied by her husband, presents with trouble walking. She describes her legs as being heavy and stiff, and at times experiences muscle spasms in her lower extremities. Her husband notices that she has been having trouble writing, and buttoning her shirt. These symptoms have progressively worsened over that past 4-5 months. Neurologic exam is significant for intrinsic hand weakness, and arm fasciculations. The lower extremity is hypertonic, with increased patellar reflexes. On gait testing, the patient has poor balance, moves slowly, and has issues with turning. Which of the following is the best treatment to prolong life?
- A. Pyridostigmine
- B. Botulinum toxin
- C. Prednisone
- D. Riluzole
Correct Answer: D
Rationale: Riluzole is the only FDA-approved medication shown to prolong life in patients with amyotrophic lateral sclerosis (ALS). It works by reducing glutamate-induced excitotoxicity, which is thought to contribute to motor neuron degeneration. Pyridostigmine is used for myasthenia gravis, botulinum toxin for spasticity, prednisone for inflammatory conditions, and intravenous immunoglobulin for autoimmune disorders. None of these treatments have been shown to prolong life in ALS.
How do spinal nerves of the peripheral nervous system (PNS) differ from cranial nerves (CNs)?
- A. Only spinal nerves occur in pairs.
- B. CNs affect only the sensory and motor functions of the head and neck.
- C. Cell bodies of all CNs are located in the brain whereas cell bodies of spinal nerves are located in the spinal cord.
- D. All spinal nerves contain both afferent sensory and efferent motor fibers whereas CNs contain one or the other or both.
Correct Answer: D
Rationale: Spinal nerves always contain both sensory and motor fibers, while cranial nerves can vary.
An elderly client has undergone electromyography tests to evaluate muscle weakness and deterioration. The client complains of slight pain after the tests. Which of the following nursing interventions would help relieve the client's discomfort?
- A. Administering topical analgesics to the area where the needle electrodes were inserted
- B. Massaging the area where the needle electrodes were inserted
- C. Applying a cold pack to the area where the needle electrodes were inserted
- D. Applying warm compresses to the area where the needle electrodes were inserted
Correct Answer: C
Rationale: Cold packs can help reduce inflammation and numb the area, relieving discomfort.
Nurse Cooper is preparing a teaching plan for a client who has started taking levodopa for Parkinson's disease. She plans to educate the client about common side effects associated with this medication. Which side effect should Nurse Cooper include in her teaching plan?
- A. Postural hypotension
- B. Development of a peptic ulcer
- C. Experiencing significant weight loss
- D. Occurrence of pancytopenia
Correct Answer: A
Rationale: Postural hypotension is a common side effect of levodopa, requiring patients to rise slowly from sitting or lying positions to prevent falls.