Nokea
With an action potential, depolarization of the axomembrane is recorded as the gates open, allowing ________ to flow into the axon.
- A. potassium ions
- B. H+ ions
- C. sodium ions
- D. all of the above
Correct Answer: C
Rationale: During the depolarization phase of an action potential, voltage-gated sodium channels open, allowing sodium ions to flow into the axon. This influx of positively charged ions causes the membrane potential to become more positive, leading to the rapid rise in voltage observed during an action potential. Sodium ion influx is essential for initiating and propagating nerve impulses.
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What is a disadvantage of open reduction and internal fixation of a fracture compared to closed reduction?
- A. Infection
- B. Skin irritation
- C. Nerve impairment
- D. Complications of immobility
Correct Answer: A
Rationale: Open reduction involves surgery, which increases the risk of infection.
A 35 year-old reporter presents to your office for evaluation of back pain and weakness in his left leg. He was play-wrestling with his nephew and hurt his back 2 weeks ago. He states that he has noticed tingling in his left leg as well. He has not noticed incontinence of bowel or bladder function. You perform a physical examination and confirm that he is dragging his left foot when he walks and that his Achilles reflex is diminished. The diagnosis is a herniated disc. Which nerve root are you testing with the Achilles reflex?
- A. C5, C6
- B. L2, L3, L4
- C. S1, S2
- D. L4, L5
Correct Answer: C
Rationale: The Achilles reflex tests the S1 and S2 nerve roots. A diminished Achilles reflex may indicate a herniated disc compressing these nerve roots. C5, C6, L2, L3, L4, and L4, L5 are tested by other reflexes, such as the biceps, patellar, and brachioradialis reflexes.
When testing the patient's cranial nerves, the nurse should:
- A. Perform specific tests for each nerve, such as asking the patient to smile or follow an object with their eyes.
- B. Measure the patient's blood glucose levels.
- C. Inspect the patient's joints for swelling.
- D. Check the patient's peripheral pulses.
Correct Answer: A
Rationale: Testing cranial nerves involves specific assessments for each nerve, such as facial movements (cranial nerve VII) or eye movements (cranial nerves III, IV, and VI). Blood glucose levels, joint swelling, and peripheral pulses are unrelated to cranial nerve testing.
What is the characteristic of a ketogenic diet suggested for children with seizures?
- A. High-carbohydrate diet
- B. High-protein diet
- C. High-fat diet
- D. Low-fat diet
Correct Answer: C
Rationale: A high-fat diet induces ketosis, which can reduce seizure frequency.
What happens at the synapse?
- A. The synapse physically joins two neurons.
- B. The nerve impulse is transmitted only from one neuron to another neuron.
- C. The presynaptic terminal submits a nerve impulse through the synaptic cleft to the receptor site on the postsynaptic cell.
- D. When a presynaptic cell releases excitatory neurotransmitters, the postsynaptic cell depolarizes enough to generate an action potential.
Correct Answer: C
Rationale: The synaptic transmission involves the presynaptic terminal sending impulses across the synaptic cleft.