Quizlet HESI A2 Anatomy and Physiology

Correct Answer: B

Rationale: The correct answer is B: To break down food. The primary role of the stomach is to mechanically and chemically break down food into smaller particles through the action of stomach acid and enzymes. This process prepares the food for further digestion in the small intestine. Incorrect choices: A: To absorb nutrients - This is not the primary role of the stomach. Nutrient absorption primarily occurs in the small intestine. C: To secrete digestive enzymes - While the stomach does secrete digestive enzymes, its primary role is not just to secrete them but to use them to break down food. D: To store glucose - The stomach does not store glucose. Glucose storage primarily occurs in the liver and muscles.

Correct Answer: A

Rationale: The primary role of hemoglobin in red blood cells is to carry oxygen. Hemoglobin binds to oxygen in the lungs and transports it to tissues throughout the body. This is essential for cellular respiration and energy production. Choices B, C, and D are incorrect because hemoglobin's main function is oxygen transport, not carrying nutrients, carbon dioxide, or waste products. Oxygen transport is crucial for the body's overall function and survival.

Correct Answer: A

Rationale: The correct answer is A: To filter waste from the blood. The kidneys act as filters, removing waste products and excess substances from the blood to form urine. This process helps maintain a balance of electrolytes and fluids in the body. Option B is incorrect because the kidneys do not produce urine from scratch; they filter blood to create urine. Option C is incorrect as the kidneys do play a role in regulating blood pressure, but it is not their primary function. Option D is also incorrect because while the kidneys do help maintain fluid balance, their primary function is waste filtration.

Correct Answer: B

Rationale: The correct answer is B: Lens. The lens in the eye is responsible for focusing light on the retina by changing its shape to adjust the focal point. The cornea (A) helps to initially focus light but does not have the ability to adjust focus. The retina (C) is the light-sensitive layer that receives focused light, not the structure that focuses light. The pupil (D) regulates the amount of light entering the eye but does not focus light on the retina.

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.