An electrolyte is a mineral or salt dissolved in the body. (Write True or False)

Choice A reason: Narrow, peaked T waves are a sign of hyperkalemia, which is a high level of potassium in the blood. Potassium is an electrolyte that affects the electrical activity of the heart. Hyperkalemia can cause the T waves, which represent the repolarization of the ventricles, to become narrow and peaked, indicating a rapid and excessive repolarization.

Choice B reason: ST elevation is a sign of myocardial infarction, which is a heart attack. It indicates that the myocardium, or the heart muscle, is damaged and deprived of oxygen. ST elevation is not related to the potassium level, but rather to the coronary artery blood flow.

Choice C reason: Peaked P waves are a sign of atrial hypertrophy, which is an enlargement of the atria, the upper chambers of the heart. It indicates that the atria are under increased pressure or workload. Peaked P waves are not related to the potassium level, but rather to the atrial function.

Choice D reason: Prominent U waves are a sign of hypokalemia, which is a low level of potassium in the blood. Potassium is an electrolyte that affects the electrical activity of the heart. Hypokalemia can cause the U waves, which represent the repolarization of the Purkinje fibers, to become prominent and visible, indicating a delayed and prolonged repolarization.

Choice A reason: This is incorrect because 120 to 140 mEq/L is a low range for serum sodium, which indicates hyponatremia. Hyponatremia can cause confusion, lethargy, seizures, and coma.

Choice B reason: This is correct because 135 to 145 mEq/L is the normal range of serum sodium in adults. Sodium is essential for fluid balance, nerve transmission, and muscle contraction.

Choice C reason: This is incorrect because 150 to 160 mEq/L is a high range for serum sodium, which indicates hypernatremia. Hypernatremia can cause thirst, dry mouth, agitation, and convulsions.

Choice D reason: This is incorrect because 165 to 175 mEq/L is a very high range for serum sodium, which indicates severe hypernatremia. Severe hypernatremia can cause irreversible brain damage and death.