Quizlet HESI A2 Anatomy and Physiology

Correct Answer: B

Rationale: Platelets play a crucial role in blood clotting. When a blood vessel is damaged, platelets adhere to the site to form a plug to stop bleeding. This process is essential for wound healing and preventing excessive blood loss. Platelets do not transport oxygen (A), fight infection (C), or transport nutrients (D). Oxygen is carried by red blood cells, immune cells fight infection, and nutrients are transported by plasma and other blood components.

Correct Answer: B

Rationale: The correct answer is B: To produce hormones. Adrenal glands are responsible for producing important hormones such as cortisol, adrenaline, and aldosterone. These hormones play crucial roles in regulating metabolism, immune response, and stress levels. Choice A is incorrect because blood sugar regulation is primarily controlled by the pancreas. Choice C is incorrect as the production of red blood cells occurs in the bone marrow. Choice D is incorrect as the filtering of blood is mainly carried out by the kidneys.

Correct Answer: A

Rationale: The correct answer is A: Pineal gland. The pineal gland is located in the brain and is responsible for producing melatonin, which regulates sleep-wake cycles. Melatonin is not produced by the thyroid gland (B), pituitary gland (C), or adrenal gland (D). The thyroid gland produces hormones that regulate metabolism, the pituitary gland regulates various hormones, and the adrenal gland produces hormones like cortisol and adrenaline. Therefore, the pineal gland is the correct answer as it specifically produces melatonin.

Correct Answer: B

Rationale: The correct answer is B: To protect the body from external damage. The skin acts as a physical barrier, preventing harmful substances from entering the body and protecting internal organs. It also helps regulate body temperature to some extent, but that is not its primary function. The skin does not produce vitamin D; this is mainly done by the liver and kidneys. Red blood cells are produced in the bone marrow, not the skin.

Correct Answer: C

Rationale: The correct answer is C: To absorb oxygen and remove carbon dioxide. The main function of the respiratory system is to facilitate the exchange of gases, where oxygen is taken in and carbon dioxide is expelled. This process is essential for cellular respiration and energy production in the body. Choices A and D are incorrect because nutrient transportation and energy production are primarily carried out by the circulatory and digestive systems. Choice B is incorrect as regulating body temperature is mainly controlled by the integumentary system and thermoregulation mechanisms.