what are the three steps of the wave of excitation

HESI A2

HESI A2 Reading Comprehension V1 2024

1. What are the three steps of the 'wave of excitation'?

A. The discharge from the SA node, the peak ECG, and the excitement of the ventricle.
B. The excitement of the ventricle, the relaxing of the ventricle, and the systemic neural response.
C. The contraction of the atrium, the relaxation of the atrium, and the contraction of the ventricle.
D. The excitation of the atrium, the excitement of the ventricle, and the relaxing of the ventricle.

Correct answer: D

Rationale: The correct steps of the 'wave of excitation' are the excitation of the atrium, excitement of the ventricle, and relaxation of the ventricle. In the described process, the 'wave of excitation' starts with the discharge from the SA node, leading to the excitation of the atrium. Next, the peak ECG corresponds to the excitement of the ventricle, not its relaxation. Finally, the wave concludes with the relaxation of the ventricle, not its contraction. Therefore, choices A, B, and C are incorrect as they do not accurately describe the sequential steps of the 'wave of excitation' as presented in the extract.

2. What is the author's reason for writing the passage on the White Elephant?

A. To inform readers about Thailand's historical customs.
B. To entertain readers with the origins of the term 'white elephant.'
C. To explain the tradition of giving white elephants.
D. To criticize the tradition of giving white elephants as gifts.

Correct answer: C

Rationale: The correct answer is C: 'To explain the tradition of giving white elephants.' The passage provides historical context about the practice of giving white elephants as gifts in ancient Siam, now Thailand. It explains how white elephants were considered sacred, could not be put to work, and became a burden to the recipients. The author's purpose is to shed light on this tradition and its implications, not to inform readers about Thailand in general (choice A), entertain with fun facts (choice B), or criticize the tradition (choice D). Choices A and B are incorrect because the passage focuses specifically on the tradition of giving white elephants, not on broader aspects of Thailand or entertainment. Choice D is incorrect because the passage does not criticize the tradition but rather provides a factual account of its historical significance.

3. What is the meaning of the word delicate as used in the first paragraph?

A. Subtle
B. Fragile
C. Refined
D. Intricate

Correct answer: D

Rationale: In the context of microsurgery, the word 'delicate' refers to the intricate, precise, and fine nature of surgeries performed using microscopy. These surgeries require intricate attention to detail and precision due to the small and delicate structures involved, making 'intricate' the most appropriate synonym. 'Subtle' implies understated or not obvious, 'fragile' suggests easily broken or damaged, and 'refined' refers to something developed or improved over time, none of which fully capture the detailed and precise nature of microsurgery. Therefore, 'intricate' is the correct answer.

4. Which statement from the selection presents a fact rather than an opinion?

A. One of the worst voice qualities is harshness
B. Harsh voice qualities usually come from too much tension in the throat and jaw
C. Your voice will sound unpleasant if it is shrill, grating, hard, piercing, brassy, too loud, or too nasal
D. Because tension occurs in higher pitched voices, women tend to have shriller voices than men, which usually makes them less desirable public speakers, newscasters, or political candidates

Correct answer: B

Rationale: Statement B, 'Harsh voice qualities usually come from too much tension in the throat and jaw,' presents a fact rather than an opinion. This statement provides a clear and objective observation about the potential cause of harsh voice qualities, based on physical tension in specific areas of the body, which can be objectively measured and identified. Choice A is an opinion as it states 'One of the worst voice qualities is harshness' without providing a verifiable basis. Choice C lists subjective descriptors of an unpleasant voice without stating a definite cause. Choice D introduces a gender-based assertion about voice quality, making it an opinion rather than a factual observation.