ATI TEAS 7 Science

Correct Answer: C

Rationale: The correct answer is C: Total lung capacity. Total lung capacity is the maximum volume of air the lungs can hold after a full forced inhalation. It includes all the volumes within the lungs, such as tidal volume, inspiratory reserve volume, expiratory reserve volume, and residual volume. It is the sum of vital capacity and residual volume. Inspiratory capacity (A) is the maximum volume of air that can be inhaled after a normal exhalation. Tidal volume (B) is the volume of air inspired or expired during normal breathing. Vital capacity (D) is the maximum volume of air that can be exhaled after a maximum inhalation, not the total volume the lungs can hold.

Correct Answer: B

Rationale: Insulin is the correct answer as it is responsible for lowering blood sugar levels by promoting the uptake of glucose into cells. Glucagon raises blood sugar levels, adrenaline and cortisol are stress hormones that increase blood sugar levels. Therefore, the correct choice is B.

Correct Answer: C

Rationale: The primary function of the lymphatic system is to fight infection and remove excess fluid. Lymph nodes contain white blood cells that help fight pathogens. Lymphatic vessels collect excess fluid from tissues and transport it back to the bloodstream, aiding in immune response. Other choices are incorrect because A: Oxygen transport is primarily done by the circulatory system, B: Blood filtration is mainly carried out by the kidneys, and D: Hormone transport is primarily through the circulatory system.

Correct Answer: B

Rationale: The correct answer is B: Myosin. Myosin is the protein complex responsible for the thick filament in the sarcomere. It forms cross-bridges with actin during muscle contraction. Actin (choice A) is the thin filament in the sarcomere. Tropomyosin (choice C) is a regulatory protein that covers the myosin-binding sites on actin when the muscle is at rest. Troponin (choice D) is another regulatory protein that helps regulate muscle contraction by binding calcium ions.

Correct Answer: B

Rationale: The correct answer is B: Insulin. Insulin is responsible for regulating blood sugar levels by facilitating the uptake of glucose into cells for energy production and storage. It helps lower blood sugar levels by promoting glucose utilization. Thyroxine (A) regulates metabolism, adrenaline (C) is involved in the fight-or-flight response, and cortisol (D) regulates stress response and metabolism, but they do not directly regulate blood sugar levels like insulin does.