What is meant by the term biodiversity?

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: 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.

Correct Answer: B

Rationale: The correct answer is B: DNA. Hormone response elements are specific DNA sequences where hormone receptors bind to regulate gene expression. This binding initiates the transcription of target genes. Choices A, C, and D are incorrect because hormone response elements are not located on the cell membrane, RNA, or enzymes. The key is understanding that hormone receptors act on DNA to regulate gene expression, making choice B the most appropriate answer.

Correct Answer: B

Rationale: The correct answer is B: Inferior phrenic artery. The superior suprarenal artery arises from the inferior phrenic artery, which supplies blood to the adrenal gland. The inferior phrenic artery originates from the abdominal aorta, near the celiac trunk. It is important to note that the adrenal glands receive blood supply from multiple sources, including the inferior phrenic artery. The other choices (A: Abdominal aorta, C: Renal artery, D: Superior mesenteric artery) do not directly supply blood to the adrenal glands, making them incorrect options.

Correct Answer: D

Rationale: The correct answer is D, the thyrocervical trunk. This artery generally gives rise to the inferior thyroid artery. The thyrocervical trunk is a branch of the subclavian artery, supplying blood to the thyroid gland. The other choices are incorrect because the arch of aorta does not give rise to the inferior thyroid artery, the brachiocephalic artery does not directly supply the thyroid gland, and the external carotid artery does not typically provide blood to the thyroid gland. Therefore, the thyrocervical trunk is the most likely source for the inferior thyroid artery.