The action potential is measured in millivolts (mV) and is ranged from:
- A. -90mV to +20mV
- B. -70mV to +30mV
- C. -65mV to +40mV
- D. -30mV to +60mV
Correct Answer: C
Rationale: The action potential involves a rapid change in membrane potential, typically ranging from -65mV (resting potential) to +40mV (peak depolarization). This change is driven by the influx of sodium ions and the subsequent efflux of potassium ions. The action potential is a key mechanism for transmitting information within the nervous system, enabling neurons to communicate over long distances.
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MRS. Post is concerned about the effect of her diagnosis of systemic lupus erythematosus on childbearing. In discharge planning with Mrs. Post, you should
- A. instruct her to use an intrauterine device for birth control
- B. tell her pregnancy may cause an exacerbation of symptoms
- C. tell her that her symptoms will not change because of pregnancy
- D. instruct her to use birth control pills
Correct Answer: B
Rationale: Pregnancy can trigger lupus flares, requiring careful monitoring.
Laboratory findings that the nurse would expect to be present in the patient with RA include
- A. polycythemia.
- B. increased immunoglobulin G (IgG).
- C. decreased white blood cell (WBC) count.
- D. anti-citrullinated protein antibody (ACPA).
Correct Answer: D
Rationale: ACPA is specific to RA.
Which part of the neuron has the highest concentration of Na.
- A. dendrites
- B. cell body
- C. synaptic knobs
- D. none of them
Correct Answer: D
Rationale: The intracellular concentration of Na+ is generally low in all parts of the neuron due to the action of the Na+, K+ ATPase pump, which actively transports Na+ out of the cell. Therefore, none of the listed parts have a high concentration of Na+.
What is the major focus for care today for a patient who is 1 day post-operative after a left below-the-knee amputation?
- A. To attain pain control for phantom pain.
- B. To monitor for signs of sufficient tissue perfusion.
- C. To assist the patient to ambulate as soon as possible.
- D. To elevate the residual limb when the patient is supine.
Correct Answer: B
Rationale: Ensuring adequate tissue perfusion is critical in the immediate post-operative period to prevent complications.
True statements about aldosterone include:
- A. it increases the amount of Na+-K+ ATPase in the target cells
- B. it reduces the sodium content of the sweat
- C. it increases the acidity of urine
- D. all above
Correct Answer: D
Rationale: Aldosterone increases Na+-K+ ATPase activity in target cells, promoting sodium reabsorption and potassium excretion. It also reduces sodium loss in sweat and increases urine acidity by promoting hydrogen ion excretion. These actions help regulate electrolyte balance and blood pressure.