Which of the following drugs is used to treat infection with Plasmodium (malaria)?

Correct Answer: C

Rationale: Rationale: Chloroquine is the correct answer as it is a well-established antimalarial drug targeting Plasmodium. It works by inhibiting the parasite's ability to break down hemoglobin. Clindamycin (A), Doxycycline (B), and Penicillin (D) are not typically used for treating malaria. Clindamycin is more commonly used for anaerobic infections, Doxycycline for bacterial infections, and Penicillin for bacterial infections unrelated to malaria.

Correct Answer: B

Rationale: The correct answer is B: Inhibiting glucagon release from the pancreas. Liraglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist that stimulates insulin secretion and inhibits glucagon release, leading to improved blood glucose control. Increased insulin secretion (Choice A) is not the primary mechanism of action for liraglutide. Liraglutide does not directly affect renal glucose excretion (Choice C) or block glucose absorption in the intestine (Choice D). Inhibiting glucagon release is crucial in lowering blood glucose levels in patients with diabetes by reducing hepatic glucose output.

Correct Answer: B

Rationale: The correct answer is B: Improving insulin sensitivity in peripheral tissues. Pioglitazone is a thiazolidinedione that acts as an insulin sensitizer by increasing insulin sensitivity in peripheral tissues like muscle and fat cells. This helps the body use insulin more effectively to lower blood sugar levels. Choice A is incorrect because pioglitazone does not directly increase insulin secretion from the pancreas. Choice C is incorrect as pioglitazone does not affect glucose absorption in the intestines. Choice D is incorrect because pioglitazone does not increase renal glucose excretion.

Correct Answer: C

Rationale: The correct answer is C: Angiotensin II receptor blockers (ARBs). ARBs work by specifically targeting and blocking the angiotensin II receptors, thus preventing angiotensin II from exerting its vasoconstrictive effects. This leads to vasodilation and decreased blood pressure. A: ACE inhibitors work by inhibiting the enzyme that converts angiotensin I to angiotensin II, not by blocking the effects of angiotensin II directly. B: Calcium channel blockers work by blocking calcium channels, not specifically targeting angiotensin II receptors. D: Beta-blockers work by blocking the effects of adrenaline, not angiotensin II. In summary, the correct answer, ARBs, directly targets angiotensin II receptors to lower blood pressure, while the other choices work through different mechanisms.

Correct Answer: A

Rationale: The correct answer is A: Blocking angiotensin II receptors. Losartan is an angiotensin II receptor blocker (ARB) that works by specifically blocking the angiotensin II receptor type 1 (AT1) receptors. Angiotensin II is a potent vasoconstrictor, and by blocking its action at the receptor level, losartan helps dilate blood vessels and reduce blood pressure. This mechanism is specific to ARBs and distinguishes them from other classes of antihypertensive medications. Choice B: Inhibiting the reuptake of norepinephrine is incorrect as this mechanism is associated with drugs like tricyclic antidepressants and not losartan. Choice C: Blocking calcium channels in the blood vessels is incorrect as this mechanism is associated with calcium channel blockers like amlodipine, not losartan. Choice D: Inhibiting aldosterone secretion is incorrect as this mechanism is associated with drugs like