Anatomy HESI A2 Practice Test

Correct Answer: B

Rationale: The correct answer is B: To store and concentrate bile. The gallbladder acts as a reservoir for bile produced by the liver, which is then released into the small intestine to aid in digestion. Bile helps emulsify fats for better absorption. Choices A, C, and D are incorrect as the gallbladder does not produce bile (the liver does), detoxify harmful substances, or directly break down fats. The primary function of the gallbladder is to store and concentrate bile for efficient digestion.

Correct Answer: A

Rationale: The correct answer is A: Parathyroid gland. When under stress, hormones like cortisol and adrenaline are released primarily from the adrenal cortex and the hypothalamus-pituitary-adrenal (HPA) axis. The posterior pituitary releases oxytocin and vasopressin, which are not directly related to stress response. The parathyroid gland, on the other hand, regulates calcium levels in the blood and is not directly involved in the stress response.

Correct Answer: C

Rationale: The function of the alveoli in the lungs is to exchange gases. Oxygen from the inhaled air diffuses into the bloodstream, while carbon dioxide from the bloodstream diffuses into the alveoli to be exhaled. This exchange process is crucial for maintaining proper oxygen levels in the blood and removing carbon dioxide, a waste product. Option A is incorrect because the alveoli do not absorb oxygen but facilitate its exchange. Option B is incorrect because while the alveoli do remove carbon dioxide, their primary function is gas exchange. Option D is incorrect as the alveoli do not regulate blood pressure but are essential for gas exchange in the respiratory system.

Correct Answer: B

Rationale: The correct answer is B: Adrenal cortex. During stress, the adrenal cortex secretes cortisol and aldosterone, which help the body respond to stress. The parathyroid gland (A) regulates calcium levels, not stress hormones. The posterior pituitary gland (C) releases hormones like oxytocin and vasopressin, not stress hormones. The hypothalamus (D) plays a role in regulating the stress response by signaling the adrenal cortex to release stress hormones.

Correct Answer: A

Rationale: The primary function of the cardiovascular system is to pump blood throughout the body. This process ensures oxygen and nutrients are delivered to tissues and organs, while also removing waste products. Choice A is correct as it directly relates to the main role of the cardiovascular system. Choices B, C, and D are incorrect because although the cardiovascular system indirectly contributes to delivering nutrients, regulating body temperature, and protecting against infection through immune responses, these are not its primary functions.