ATI TEAS Science Questions

Correct Answer: B

Rationale: The correct answer is B: 'To fight infection.' The immune system's primary function is to protect the body from infections and foreign invaders by recognizing and responding to pathogens. It plays a crucial role in maintaining overall health and preventing diseases caused by harmful microorganisms. Choices A, C, and D are incorrect because the immune system is not responsible for transporting oxygen, digesting food, or producing hormones. These functions are carried out by other systems in the body, such as the respiratory system, digestive system, and endocrine system, respectively.

Correct Answer: B

Rationale: Liters are the best unit to measure the amount of blood in the human body because blood volume is typically measured in liters in the medical field. Using liters provides a standardized and accurate measurement of the significant amount of blood in the human body, which is typically around 5-6 liters for an average-sized adult. Other units like ounces, milliliters, and pounds are not commonly used to measure blood volume in clinical settings. Ounces are too small a unit for measuring blood volume, milliliters are less commonly used in this context compared to liters, and pounds are a unit of weight rather than volume.

Correct Answer: B

Rationale: Smooth muscle is the correct type of muscle found in the walls of hollow organs like the intestines. It is responsible for movements such as peristalsis, aiding in the movement of food and other materials through the digestive system. Cardiac muscle (Choice A) is found in the heart and is responsible for the heart's contractions, not in hollow organs like the intestines. Skeletal muscle (Choice C) is attached to bones and responsible for voluntary movements, not in hollow organ walls. Voluntary muscle (Choice D) is another term for skeletal muscle, which is under conscious control, unlike smooth muscle in hollow organ walls.

Correct Answer: B

Rationale: The correct answer is B: Ossicles. The ossicles, consisting of the malleus, incus, and stapes, are located in the middle ear. They play a crucial role in transmitting sound vibrations from the eardrum to the inner ear, specifically to the cochlea. The cochlea is responsible for converting sound vibrations into electrical signals for the brain to interpret. The semicircular canals are not involved in transmitting sound but are responsible for balance and orientation. The eustachian tube's function is to help equalize pressure in the middle ear, not to transmit sound vibrations.

Correct Answer: C

Rationale: The corrected answer is C. Elastic arteries, like the aorta, are the largest arteries in the body. They possess elastic fibers in their walls, allowing them to stretch and recoil in response to the pulsatile nature of blood flow from the heart. This elasticity helps to maintain blood pressure by absorbing the pressure waves generated by the heart's contractions and ensuring continuous blood flow to the organs. Choices A, B, and D are incorrect because elastic arteries are not the smallest arteries, do not constrict and dilate frequently, are not medium-sized arteries for distributing blood to various organs, and are not thin-walled arteries supplying blood to capillaries. Elastic arteries have a specific structure and function related to their ability to accommodate blood pressure changes due to their elastic properties, which is essential for the cardiovascular system's proper functioning.