HESI A2 Reading Comprehension V1 2024

Correct Answer: C

Rationale: The correct answer is C because it accurately summarizes the key points of the passage about the ECG. It mentions that the ECG measures the stages of the 'wave of excitation' within the heart and its three distinct steps. It also describes how this wave spreads from the SA node to the AV node. Choice A is incorrect because it focuses on electrostatic charges set off by the heart, which is not the main focus of the passage. Choice B is incorrect because it talks about unique electric currents on the surface of the body, which is not the main purpose of the ECG as mentioned in the passage. Choice D is incorrect because it only mentions that the ECG measures electric currents within the body without providing the specifics of the wave of excitation and its stages as described in the passage.

Correct Answer: D

Rationale: The correct answer is D because it accurately describes the three steps of the 'wave of excitation' in the heart. 1. The excitation of the atrium: This step involves the initiation of the electrical signal in the atria, leading to their contraction. 2. The excitement of the ventricle: Following the excitation of the atrium, the electrical signal spreads to the ventricles, causing them to contract. 3. The relaxing of the ventricle: Once the ventricles have contracted and ejected blood, they then relax in preparation for the next cardiac cycle. Choice A is incorrect because it mentions the peak ECG, which is not a step in the 'wave of excitation.' Choice B is incorrect as it includes systemic neural response, which is not part of the electrical conduction pathway. Choice C is incorrect as it describes the contraction and relaxation of the atrium only, missing the crucial step of ventricular excitation.

Correct Answer: B

Rationale: The correct answer is B: Releasing. In the context of the second paragraph, 'emitting' refers to giving off or releasing something, which aligns with the overall meaning of the paragraph. 'Repelling' (A) means to push away, 'Closing' (C) means to shut or block, and 'Charging' (D) means to energize with electricity - these choices do not fit the context of the paragraph. Therefore, B is the most suitable choice based on the definition and context of the word 'emitting.'

Correct Answer: C

Rationale: The correct answer is C because the author's primary purpose is to inform the reader about how an electrocardiograph reads the electric currents emitted by the heart. This is evident as the essay likely discusses the technical aspects of electrocardiography. Choice A is incorrect because there is no indication of persuasion in the essay. Choice B is incorrect as the focus is not on entertaining but on providing information. Choice D is incorrect as the essay is not about analyzing the differences between specific nodes in the heart.

Correct Answer: A

Rationale: The correct answer is A: call into service. In the context of the second paragraph, 'enlist' means to join or sign up for a particular cause or service. This is evident from the sentence mentioning individuals joining the army. Choice B, write down, is incorrect because 'enlist' doesn't refer to simply writing something. Choice C, send away, is incorrect as it implies the opposite meaning of 'enlist.' Choice D, put across, is also incorrect as it does not capture the idea of joining or signing up as 'enlist' does.