Anatomy HESI A2 Practice Test

Correct Answer: A

Rationale: The correct answer is A: Vitamin A. Vitamin A is essential for vision as it plays a crucial role in the function of the retina and helps maintain a healthy cornea. It is also important for skin health by promoting skin cell growth and repair. Vitamin C (B) is important for immune function and collagen synthesis, not specifically for vision or skin health. Vitamin D (C) is crucial for bone health and immune function. Vitamin E (D) is an antioxidant that helps protect cells from damage, but it is not specifically essential for vision or skin health.

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: Hinge. The elbow joint is a hinge joint because it allows movement in only one plane, similar to a door hinge. It primarily enables flexion and extension movements. A: Ball and socket joints, like the hip joint, allow for a wider range of motion in multiple planes. C: Pivot joints, found in the neck, allow for rotational movements. D: Saddle joints, like the thumb joint, have a more complex shape that permits a variety of movements, but not present at the elbow.

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: B

Rationale: The correct answer is B: Vitamin D. Vitamin D is essential for bone health as it helps the body absorb calcium, a crucial mineral for bone strength. Without sufficient Vitamin D, the body cannot utilize calcium efficiently, leading to weakened bones. Explanation of incorrect choices: A: Vitamin A is important for vision and immune function, but it is not directly related to bone health. C: Vitamin C is vital for collagen production and immune function, but it does not play a direct role in bone health. D: Vitamin K is necessary for blood clotting and bone mineralization, but Vitamin D is more critical for calcium absorption, making it the better choice for bone health.