Which of the following is an alpha-blocker used in the treatment of hypertension:

Correct Answer: B

Rationale: Step 1: Understand the question is about an alpha-blocker for hypertension. Step 2: Identify Prazosin as an alpha-blocker used for hypertension by blocking alpha-1 receptors. Step 3: Explain how Prazosin works to dilate blood vessels and lower blood pressure. Step 4: Summarize why other choices are incorrect: - A: Tyramine is not an alpha-blocker, it is found in certain foods. - C: Ergometrine is an ergot alkaloid used for uterine contractions, not hypertension. - D: Ergotamine is also an ergot alkaloid used for migraines, not hypertension.

Correct Answer: C

Rationale: The correct answer is C: Reduced blood pressure, hypotension. Quinidine's strong postsynaptic alpha-adrenergic receptor blocking activity would result in decreased activation of these receptors, leading to vasodilation and reduced blood pressure, which can cause hypotension. Choice A is incorrect because lacrimal and mucus secretions are not directly affected by alpha-adrenergic receptor blocking. Choice B is incorrect as dilated pupils are more associated with alpha-1 adrenergic receptor blockade. Choice D is incorrect as skeletal muscle tremors are not a typical side effect of alpha-adrenergic receptor blocking.

Correct Answer: D

Rationale: The correct answer is D because biodiversity refers to the variety of living organisms in an ecosystem, specifically the number of different species present. This term encompasses all forms of life, from bacteria to plants to animals. Choice A is incorrect as it only focuses on the increase in the number of species, not the overall diversity. Choice B is incorrect as it describes the interaction between organisms and their environment, not the diversity of species. Choice C is incorrect as it limits biodiversity to only animals, neglecting the importance of other living organisms in an ecosystem.

Correct Answer: C

Rationale: When aqueous silver nitrate is added to a mixture, a yellow precipitate forms if there are chloride ions present. This is due to the formation of silver chloride, which is insoluble in water. The reaction is AgNO3 + Cl- → AgCl↓ + NO3-. Therefore, choice C is correct. Choice A (white precipitate) is incorrect because silver chloride is yellow, not white. Choice B (white solution) is incorrect as a precipitate forms, not a solution. Choice D (yellow solution) is incorrect because the product is a solid precipitate, not a solution.

Correct Answer: C

Rationale: The correct answer is C: kidneys. The kidneys are not considered a major endocrine organ, but they do produce hormones such as erythropoietin and renin as part of their major function of regulating fluid balance and blood pressure. The pancreas (A) is a major endocrine organ producing insulin and glucagon. The thymus (B) is involved in immune function and produces hormones like thymosin. The pituitary (D) is often referred to as the master gland and secretes various hormones that regulate other endocrine glands.