Nokea
The resting membrane potential of a cell
- A. is dependent on the permeability of the cell membrane to K+ being greater than the permeability to Na+
- B. falls to zero immediately when Na+, K+ ATPase in the membrane is inhibited
- C. is usually equal to the equilibrium potential for K+
- D. is usually equal to the equilibrium potential for Na+
Correct Answer: A
Rationale: The resting membrane potential is primarily determined by the permeability of the cell membrane to potassium ions (K+), which is greater than its permeability to sodium ions (Na+). This is because the membrane has more leak channels for K+ than for Na+, allowing K+ to diffuse out of the cell, creating a negative intracellular environment. The Na+, K+ ATPase pump maintains this gradient but does not directly set the resting potential. Inhibition of the pump would eventually disrupt the gradient, but the potential does not immediately fall to zero.
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Nurse Harris is providing lifestyle and safety advice to Mr. Baker, a patient with Parkinson's disease. She wants to ensure that Mr. Baker avoids activities that might exacerbate his symptoms or pose a risk to his health. Which of the following should Nurse Harris advise Mr. Baker to avoid?
- A. Participating in seated yoga classes.
- B. Walking on uneven terrain alone.
- C. Eating a balanced diet rich in fiber.
- D. Engaging in mild stretching exercises.
Correct Answer: B
Rationale: Walking on uneven terrain alone increases the risk of falls for PD patients due to postural instability and gait disturbances.
The nurse teaches the patient with RA that which exercise is one of the most effective methods of aerobic exercise?
- A. Ballet dancing
- B. Casual walking
- C. Aquatic exercises
- D. Low-impact aerobic exercises
Correct Answer: C
Rationale: Aquatic exercises reduce joint stress.
A previously healthy 68-year-old male presents with progressive muscle weakness in his right hand, swallowing difficulty and difficulty with walking. He believes these symptoms occurred "out of the blue" and have worsened over the last 2-3 months. His temperature is 98.6 deg F (37 deg C), blood pressure 145/86 mmHg, pulse is 80/min, and respirations are 17/min. Neurologic examination is significant for mild dysarthria. He has atrophy of the thenar muscles of the right hand and forearm, and 2/5 strength on wrist extension and flexion, as well as 3/5 power in intrinsic hand muscles on right. He has some fasciculations in his right thigh, and mild (4+/5) weakness of hip flexors bilaterally. Tone is increased in both legs. Sensory examination is intact. 3+ patellar reflexes are noted on the left lower extremity. On gait testing, the patient has poor balance, and spastic gait. Which of the following is the most likely diagnosis?
- A. Guillain-Barre syndrome
- B. Amyotrophic lateral sclerosis
- C. Myasthenia gravis
- D. Multiple sclerosis
Correct Answer: B
Rationale: The patient's presentation of progressive muscle weakness, atrophy, fasciculations, and spasticity with hyperreflexia is classic for amyotrophic lateral sclerosis (ALS). ALS involves both upper and lower motor neuron degeneration, leading to a combination of weakness, atrophy, and spasticity. The absence of sensory deficits and the presence of bulbar symptoms (dysarthria, swallowing difficulty) further support this diagnosis. Guillain-Barre syndrome typically presents with ascending paralysis and areflexia, while myasthenia gravis is characterized by fatigable weakness without atrophy or fasciculations. Multiple sclerosis and dermatomyositis do not fit the clinical picture.
In the UK, two tests of speed of information processing, verbal memory tests (list learning and story recall), and visual memory tests (design learning and figure recall) is known as:
- A. The Adult Memory and Information Processing Battery (AMIPB).
- B. The Information Processing test (IPT).
- C. The Adult Executive Function Scale (AEFS).
- D. The Memory Battery (MB).
Correct Answer: A
Rationale: The Adult Memory and Information Processing Battery (AMIPB) is a comprehensive neuropsychological test used in the UK to assess memory and information processing abilities. It includes tests of verbal memory (e.g., list learning, story recall) and visual memory (e.g., design learning, figure recall), as well as measures of processing speed. This battery is widely used to evaluate cognitive functioning in individuals with neurological disorders or brain injuries.
What surgical treatment will the nurse prepare the patient for in the presence of compartment syndrome?
- A. Fasciotomy
- B. Amputation
- C. Internal fixation
- D. Release of tendons
Correct Answer: A
Rationale: Fasciotomy relieves pressure in compartment syndrome.