Correct Answer: C

Rationale: This is incorrect because intracellular fluid is greater than extracellular fluid in a hypertonic state, not an isotonic state. A hypertonic state is when the solute concentration of the extracellular fluid is higher than the intracellular fluid, which causes water to move out of the cells and shrink them. This is incorrect because extracellular fluid is less than intracellular fluid in a hypotonic state, not an isotonic state. A hypotonic state is when the solute concentration of the extracellular fluid is lower than the intracellular fluid, which causes water to move into the cells and swell them. This is correct because intracellular and extracellular fluid is equal in an isotonic state. An isotonic state is when the solute concentration of the extracellular fluid is the same as the intracellular fluid, which causes no net movement of water across the cell membrane. This is incorrect because interstitial fluid is less than the transcellular fluid in a situation of fluid imbalance, not an isotonic state. Interstitial fluid is the fluid that surrounds the cells, while transcellular fluid is the fluid that is contained in specialized cavities, such as cerebrospinal fluid, synovial fluid, or pleural fluid.

Correct Answer: B

Rationale: This is incorrect because filtration is a passive transport mechanism that does not require cellular energy. Filtration is the movement of fluid and solutes across a membrane due to hydrostatic pressure. This is correct because active transport is a transport mechanism that requires cellular energy in the form of ATP. Active transport is the movement of molecules across a membrane against their concentration gradient, using carrier proteins. This is incorrect because diffusion is a passive transport mechanism that does not require cellular energy. Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration, until equilibrium is reached. This is incorrect because osmosis is a passive transport mechanism that does not require cellular energy. Osmosis is the movement of water across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Correct Answer: A

Rationale: This is correct because respiratory acidosis is a condition where the blood pH is lower than the normal range of 7.35 to 7.45, due to impaired gas exchange or hypoventilation, which causes carbon dioxide to accumulate in the blood. COPD is a chronic lung disease that obstructs the airways and reduces the oxygen intake and carbon dioxide output. This leads to respiratory acidosis in the patient. This is incorrect because respiratory alkalosis is a condition where the blood pH is higher than the normal range of 7.35 to 7.45, due to hyperventilation, which lowers the carbon dioxide in the blood. COPD does not cause hyperventilation, but rather hypoventilation. This is incorrect because metabolic alkalosis is a condition where the blood pH is higher than the normal range of 7.35 to 7.45, due to a loss of acids or an excess of bases in the body. COPD does not affect the metabolic system directly, but rather the respiratory system. This is incorrect because metabolic acidosis is a condition where the blood pH is lower than the normal range of 7.35 to 7.45, due to an excess of acids or a loss of bases in the body. COPD does not affect the metabolic system directly, but rather the respiratory system.

Correct Answer: D

Rationale: This is incorrect because normal saline is not indicated for this client. Normal saline is a isotonic solution that does not alter the acid-base balance. The client has respiratory alkalosis, which is caused by hyperventilation and results in a high pH and a low PaCO2. This is incorrect because Allen's test is not relevant for this client. Allen's test is a test to assess the patency of the radial and ulnar arteries before performing an arterial blood gas (ABG) sampling or cannulation. The client already has ABG results, so there is no need to perform Allen's test. This is incorrect because increasing breathing would worsen the client's condition. Increasing breathing would cause the client to exhale more carbon dioxide, which would lower the PaCO2 and raise the pH even more. This would increase the severity of respiratory alkalosis. This is correct because slowing down breathing would help the client to correct the respiratory alkalosis. Slowing down breathing would allow the client to retain more carbon dioxide, which would increase the PaCO2 and lower the pH. This would bring the acid-base balance closer to normal.

Correct Answer: D

Rationale: This is incorrect because the adrenal gland is not involved in the thirst mechanism. The adrenal gland is responsible for producing hormones such as cortisol, aldosterone, and adrenaline, which regulate stress response, blood pressure, and metabolism. This is incorrect because the cerebral cortex is not involved in the thirst mechanism. The cerebral cortex is the outer layer of the brain that is responsible for higher cognitive functions such as memory, language, and reasoning. This is incorrect because the pituitary gland is not directly involved in the thirst mechanism. The pituitary gland is a small gland at the base of the brain that produces hormones that control growth, reproduction, and metabolism. However, the pituitary gland does secrete antidiuretic hormone (ADH), which is regulated by the hypothalamus and affects water balance in the body. This is correct because the hypothalamus is the location of the thirst mechanism. The hypothalamus is a part of the brain that regulates many bodily functions such as temperature, appetite, sleep, and emotions. The hypothalamus also monitors the blood osmolarity and triggers the sensation of thirst when the blood is too concentrated.