Quizlet HESI A2 Anatomy and Physiology

Correct Answer: B

Rationale: The correct answer is B: Pharynx. The pharynx is a structure found in the upper respiratory tract, specifically connecting the nasal cavity and the larynx. It serves as a passage for air and food. The larynx (A) is also part of the upper respiratory tract, housing the vocal cords. The esophagus (C) is part of the digestive system, not the respiratory tract. The trachea (D) is located below the larynx and is considered part of the lower respiratory tract. Therefore, the pharynx is the correct choice for a structure found in the upper respiratory tract.

Correct Answer: B

Rationale: The correct answer is B: Heart. The heart is not a component of the central nervous system (CNS) as it is part of the cardiovascular system. The CNS consists of the brain, spinal cord, and retina. The brain controls cognitive functions, the spinal cord transmits nerve signals, and the retina is a part of the visual system. Choice B is incorrect as the heart's function is to pump blood and is not involved in CNS functions.

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: A

Rationale: Vitamin C is the correct answer as it enhances the absorption of non-heme iron found in plant-based foods. It forms a strong bond with iron, making it easier for the body to absorb. Vitamin D helps with calcium absorption, Vitamin K is crucial for blood clotting, and Vitamin B12 is important for nerve function and red blood cell production. However, they do not directly assist in iron absorption like Vitamin C does.

Correct Answer: B

Rationale: The correct answer is B: To exchange gases. Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide takes place. Oxygen from the air we breathe enters the blood through the alveoli, and carbon dioxide is removed from the blood and exhaled. This process is essential for respiration. Explanation of other choices: A: To filter blood - This is incorrect because the alveoli do not filter blood. Filtering of blood primarily occurs in the kidneys and liver. C: To transport nutrients - This is incorrect because the alveoli are not involved in transporting nutrients. Nutrient transport mainly occurs through the bloodstream. D: To store oxygen - This is incorrect because the alveoli do not store oxygen. Oxygen is temporarily stored in the red blood cells and muscle tissues.