Nokea
Which of the following best describes the waxy-appearing material called myelin:
- A. an outermembrane on a neuroglial cell
- B. a lipid-protein (lipoprotein) cell membrane on the outside of axons
- C. a mass of white lipid material that surrounds the cell body of a neuron
- D. a mass of white lipid material that insulates the axon of a neuron
Correct Answer: D
Rationale: Myelin is a lipid-rich substance that forms a sheath around axons, providing insulation and increasing the speed of nerve impulse transmission. It does not surround the cell body or dendrites, making D the correct answer.
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Which myotome is responsible for shoulder abduction
- A. C4
- B. C5
- C. C6
- D. C7
Correct Answer: B
Rationale: The C5 and C6 nerve roots innervate the deltoid and supraspinatus muscles, which are responsible for shoulder abduction. This is important in assessing brachial plexus injuries.
To assess a patient's recent memory, the nurse should:
- A. Ask the patient to recall recent events or conversations.
- B. Check the patient's ability to recognize familiar faces.
- C. Measure the patient's blood pressure.
- D. Inspect the patient's gait.
Correct Answer: A
Rationale: Recent memory is assessed by asking the patient to recall recent events or conversations. Recognizing faces, blood pressure, and gait are unrelated to memory assessment.
The 4th cranial nerve supplies
- A. Lateral rectus
- B. Inferior oblique
- C. Orbicularis oris
- D. Superior oblique
Correct Answer: D
Rationale: The trochlear nerve (IV) innervates the superior oblique muscle, which depresses and abducts the eye. It is the only cranial nerve that exits dorsally from the brainstem.
What are the two major physical changes in the brain that are characteristic of Alzheimer's disease?
- A. aluminum deposition and edema
- B. amyloid plaques and neurofibrillary tangles
- C. amyloid plaques and hypertrophy
- D. calcification and hypertrophy
Correct Answer: B
Rationale: Alzheimer's disease is characterized by the accumulation of amyloid plaques (abnormal protein deposits) and neurofibrillary tangles (twisted fibers of tau protein) in the brain. These changes disrupt neuronal communication and lead to cognitive decline.
Which of the following practices would delay the decline in muscle strength and bone mass in older adults?
- A. Maintaining an adequate calcium intake
- B. Maintaining an active lifestyle
- C. Maintaining a low-activity lifestyle after the age of 35
- D. Reducing the calcium intake after the age of 60
Correct Answer: B
Rationale: An active lifestyle helps maintain muscle strength and bone mass.