A 55-year-old male with a 30-year history of smoking is examined for respiratory disturbance. Examination of his airway (bronchial) reveals that stratified squamous epithelial cells have replaced the normal columnar ciliated cells. This type of cellular adaptation is called:

Choice A Reason:

Decreased ATP production is the primary cause of sodium and water accumulation in an injured cell. ATP is essential for the function of the sodium-potassium (Na±K+) pump, which maintains the ionic balance within the cell. When ATP levels drop, the Na±K+ pump fails, leading to an influx of sodium and water into the cell, causing cellular swelling.

Choice B Reason:

Calcification of the cell refers to the abnormal deposition of calcium salts within the cell. While calcification can occur in injured cells, it is not directly responsible for sodium and water accumulation. Calcification is more related to chronic injury and cell death rather than acute cellular swelling.

Choice C Reason:

Ribosome detachment from the endoplasmic reticulum can occur due to cellular stress and injury, leading to reduced protein synthesis. However, this detachment is not the direct cause of sodium and water accumulation. The primary issue is the failure of the Na±K+ pump due to decreased ATP production.

Choice D Reason:

Dehydration refers to the loss of water from the body or cells. While dehydration can affect cellular function, it is not the cause of sodium and water accumulation in injured cells. The accumulation is primarily due to the failure of the Na±K+ pump, which is dependent on ATP.

Choice A Reason:

The statement that the medication will be completely out of the patient’s body after three days is incorrect. The half-life of a drug indicates the time it takes for the concentration of the drug in the body to reduce by half. After one half-life (one day), 50% of the drug remains. After two half-lives (two days), 25% remains. After three half-lives (three days), 12.5% remains. Therefore, some amount of the drug will still be present in the body after three days.

Choice B Reason:

To calculate the amount of medication remaining after three days, we use the half-life formula. Starting with 10 mg, after one day (one half-life), 5 mg remains. After two days (two half-lives), 2.5 mg remains. After three days (three half-lives), 1.25 mg remains. This calculation shows that 1.25 mg of the medication will still be in the patient’s body after three days.

Choice C Reason:

The choice of 5 mg is incorrect because it represents the amount of medication remaining after one half-life (one day), not three half-lives. After one day, 50% of the initial dose remains, which is 5 mg. However, the question asks for the amount remaining after three days.

Choice D Reason:

The choice of 1 mg is also incorrect. After three half-lives, the amount of medication remaining is 12.5% of the initial dose. For an initial dose of 10 mg, this would be 1.25 mg, not 1 mg. The calculation must accurately reflect the reduction by half for each half-life period.