Practice TEAS Science Test

Correct Answer: B

Rationale: The correct answer is B: Laryngopharynx. The laryngopharynx is part of the pharynx where both the respiratory and digestive systems intersect. It serves as a common passageway for both food and air. When we swallow, the epiglottis covers the larynx to prevent food from entering the trachea. A: The esophagus is solely a passageway for food from the mouth to the stomach. C: The nasopharynx is a part of the upper respiratory tract and not involved in the passage of food. D: The trachea is strictly a passageway for air to enter and exit the lungs.

Correct Answer: B

Rationale: The correct answer is B: To absorb water and form feces. The large intestine mainly functions to absorb water from the indigestible food residue and solidify it into feces before excretion. This process helps in maintaining the body's fluid balance and preventing dehydration. Why the other choices are incorrect: A: The absorption of proteins primarily occurs in the small intestine, not the large intestine. C: Enzymes for digestion are produced in the pancreas and small intestine, not in the large intestine. D: Fat storage is mainly regulated by adipose tissue throughout the body, not the large intestine.

Correct Answer: A

Rationale: Insulin is the correct answer as it helps regulate blood sugar levels by facilitating the uptake of glucose into cells. Adrenaline, cortisol, and melatonin do not directly regulate blood sugar levels like insulin does. Adrenaline primarily affects the fight-or-flight response, cortisol is involved in stress response and metabolism, and melatonin regulates sleep-wake cycles. Insulin's role in blood sugar regulation is crucial for maintaining proper glucose levels in the body.

Correct Answer: B

Rationale: The correct answer is B: Depolarization of the SA node. The P-wave in an ECG represents atrial depolarization, which is initiated by the SA node. This electrical signal spreads through the atria causing them to contract. Choice A is incorrect because the P-wave corresponds to atrial depolarization, not repolarization. Choice C is incorrect as the QRS complex represents ventricular depolarization. Choice D is incorrect as the T-wave represents ventricular repolarization. Therefore, the SA node depolarization is accurately represented by the P-wave in an ECG.

Correct Answer: D

Rationale: The correct answer is D: Epiglottis. The epiglottis is a flap of tissue that covers the opening of the windpipe (trachea) during swallowing to prevent food from entering it. Step-by-step rationale: 1. During swallowing, the epiglottis moves down to cover the trachea. 2. This action directs food to the esophagus (B), a muscular tube that carries food to the stomach. 3. The pharynx (A) is a common passageway for both food and air but does not prevent food from entering the windpipe. 4. The larynx (C) is involved in sound production but does not prevent food from entering the windpipe. In summary, the epiglottis is the correct structure as it specifically functions to protect the windpipe during swallowing, while the other choices do not have this specific function.