Anatomy and Physiology Hesi A2 Practice Test

Correct Answer: B

Rationale: The correct answer is B: Left ventricle. The left ventricle is the largest and strongest chamber of the heart because it is responsible for pumping oxygenated blood to the entire body. It has thick muscular walls to generate enough force to propel blood through the systemic circulation. The right atrium (choice A) receives deoxygenated blood from the body, the right ventricle (choice C) pumps this blood to the lungs for oxygenation, and the left atrium (choice D) receives oxygenated blood from the lungs. None of these chambers have the same pumping workload and muscular thickness as the left ventricle, making it the correct answer.

Correct Answer: B

Rationale: The correct answer is B: To protect against pathogens. The skin acts as a physical barrier that prevents harmful pathogens from entering the body. It also contains specialized immune cells that help to fight off infections. Vitamin D production (choice A) primarily occurs in the skin but is not the main function of skin protection. Storing nutrients (choice C) is not a primary function of the skin. While the skin does play a role in thermoregulation (choice D), its main function in protecting the body is to defend against pathogens.

Correct Answer: B

Rationale: The correct answer is B: Vitamin A. Step 1: Vitamin A is essential for maintaining healthy skin as it promotes cell growth and repair. Step 2: Vitamin A is crucial for vision as it is a component of rhodopsin, a protein in the retina. Step 3: Vitamin C (choice A) is important for immune function and collagen production, not specifically skin or vision. Vitamin D (choice C) is essential for bone health, not skin or vision. Vitamin K (choice D) is important for blood clotting, not skin or vision.

Correct Answer: B

Rationale: The correct answer is B: Endocrine glands secrete chemicals into the blood. This is because endocrine glands release hormones directly into the bloodstream to regulate various physiological functions throughout the body. Other choices are incorrect: A is incorrect as endocrine glands do not absorb chemicals from the blood; C is incorrect because endocrine glands do not filter chemicals from the blood; and D is incorrect as endocrine glands do not absorb chemicals from the lymphatic system.

Correct Answer: A

Rationale: The correct answer is A: Cochlea. The cochlea is responsible for hearing as it contains the hair cells that convert sound vibrations into electrical signals sent to the brain. Semicircular canals are responsible for balance, ossicles transmit sound waves, and the Eustachian tube regulates air pressure in the ear. Cochlea is the only structure directly involved in the process of hearing.