Anatomy HESI A2 Practice Test

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: 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: 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.

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.

Correct Answer: B

Rationale: The correct answer is B: Detoxifying harmful substances. The liver plays a crucial role in filtering and detoxifying harmful substances like drugs, alcohol, and metabolic waste products. It metabolizes these substances to make them less harmful for elimination from the body. This function is essential for maintaining overall health and preventing damage to other organs. Incorrect Choices: A: Producing insulin - The pancreas is responsible for producing insulin, not the liver. C: Digesting food - The liver produces bile that aids in digestion, but its primary role is not digesting food. D: Storing energy - While the liver does store glycogen as an energy reserve, its primary role is not storing energy.