HESI A2 Anatomy and Physiology Practice Test 2023

Correct Answer: A

Rationale: The correct answer is A: Vitamin C. Collagen synthesis requires Vitamin C as it is essential for the hydroxylation of proline and lysine residues in collagen, which stabilizes the collagen structure. Vitamin D (choice B) is important for calcium absorption and bone health. Vitamin B12 (choice C) is crucial for nerve function and red blood cell production. Vitamin K (choice D) is necessary for blood clotting. However, for collagen synthesis specifically, Vitamin C is the key nutrient.

Correct Answer: B

Rationale: The correct answer is B: To break down food. The stomach's main function is to mechanically and chemically break down food through the action of stomach acids and enzymes. This process prepares the food for further digestion in the small intestine. Option A is incorrect because nutrient absorption primarily occurs in the small intestine, not the stomach. Option C is incorrect as bile is produced by the liver and stored in the gallbladder, not the stomach. Option D is incorrect because waste storage occurs in the large intestine, not the stomach. The process of breaking down food in the stomach is essential for the efficient absorption of nutrients in the digestive system.

Correct Answer: B

Rationale: The correct answer is B: Hippocampus. The hippocampus is a key brain region involved in memory formation due to its role in encoding, storing, and retrieving memories. It plays a crucial role in both short-term and long-term memory processes. Damage to the hippocampus can result in amnesia, further emphasizing its importance in memory formation. Incorrect choices: A: Cerebellum - Primarily involved in motor control and coordination. C: Brainstem - Regulates basic life functions such as breathing and heart rate. D: Frontal lobe - Responsible for executive functions, decision-making, and personality. While it plays a role in memory retrieval, it is not primarily involved in memory formation.

Correct Answer: C

Rationale: The correct answer is C: Kidneys. The kidneys are responsible for filtering and cleaning the blood through the process of removing waste products, excess fluids, and toxins, which are then excreted as urine. The kidneys play a crucial role in maintaining the body's overall balance of fluids and electrolytes. The other choices are incorrect because: A: Lungs are responsible for exchanging gases, not filtering blood. B: Heart is a muscular organ that pumps blood, not involved in blood filtration. D: Liver plays a role in detoxification and metabolism, but it does not directly filter blood like the kidneys do.

Correct Answer: B

Rationale: The correct answer is B: To secrete digestive enzymes. The pancreas secretes enzymes such as amylase, lipase, and proteases that aid in breaking down carbohydrates, fats, and proteins in the small intestine. This supports the digestion and absorption of nutrients. Choices A, C, and D are incorrect because the pancreas does not directly absorb nutrients, produce bile, or store glucose.