Nokea
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.
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What is the author's primary purpose in writing the essay?
- A. To persuade the reader to have an ECG
- B. To entertain the reader with a heartwarming story
- C. To inform the reader how an electrocardiograph reads the electric currents emitted by the heart
- D. To analyze the difference between the SA node and the AV node
Correct Answer: C
Rationale: The author's primary purpose in writing the essay is to inform the reader about how an electrocardiograph reads the electric currents emitted by the heart. Choice A is incorrect because there is no attempt to persuade the reader to have an ECG. Choice B is incorrect because the essay is focused on providing information rather than entertaining with a heartwarming story. Choice D is incorrect as the essay does not primarily analyze the difference between the SA node and the AV node; instead, it focuses on explaining how an electrocardiograph reads electric currents from the heart.
Which statement is not listed as a detail within the passage?
- A. Changes in the ECG are typically used for the diagnosis of abnormal cardiac rhythm.
- B. The signal has a characteristic record called the electrocardiogram.
- C. The 'wave of excitation' starts at the SA node.
- D. The 'wave of excitation' spreads through the heart wall and is accompanied by electric changes.
Correct Answer: A
Rationale: The corrected statement should be: Changes in the ECG are not typically used for the diagnosis of abnormal cardiac rhythm. The passage mentions that the heart sends out electric currents in waves, and the 'wave of excitation' spreads through the heart wall accompanied by electric changes. It details the process of how the heart's electric impulses are recorded and how abnormalities can be detected. However, it does not state that ECG changes are specifically used for diagnosing abnormal cardiac rhythms. Choice A is the correct answer because it misrepresents the information provided in the passage. Choices B, C, and D are all supported by the passage and align with the details mentioned regarding the electrocardiogram and the wave of excitation in the heart.
What is the meaning of the word 'elasticity' in the last paragraph?
- A. Something that is able to resist and be flexible
- B. Something that is like plastic
- C. Something that is dynamic and electrifying
- D. Something that is silly
Correct Answer: A
Rationale: 'Elasticity' refers to the ability of the arterial walls to resist and be flexible, which affects blood pressure. In the provided extract, it is mentioned that an increase in blood pressure can occur if the arterial walls lose some of their elasticity with age or disease. This demonstrates that elasticity refers to the property of being able to resist and be flexible, supporting choice A as the correct answer. The other choices, B, C, and D, do not accurately reflect the concept of elasticity in the context of arterial walls and blood pressure.
What is the meaning of the word 'phenomenon' in the second paragraph?
- A. Something that is lifeless to the senses
- B. Something that is nonchalant
- C. Something that is significant but unusual
- D. Something that is chemical in origin
Correct Answer: C
Rationale: In the context of the second paragraph, 'phenomenon' refers to something significant and unusual, specifically describing the scientific phenomenon known as the Doppler Effect. This effect explains the change in frequency of sound waves when a source of sound and the observer are in relative motion. Choices A, B, and D are incorrect because they do not accurately reflect the meaning of 'phenomenon' in this context. 'Lifeless to the senses,' 'nonchalant,' and 'chemical in origin' do not align with the description of the Doppler Effect, which is a notable and uncommon scientific occurrence.
What is the meaning of the word 'composed' in the first paragraph?
- A. To consist of
- B. To be uniquely discovered
- C. To be set apart
- D. To be surprised
Correct Answer: A
Rationale: In the context provided, 'composed' means to consist of. The paragraph explains that a drop of water is composed of an oxygen atom and two hydrogen atoms. Therefore, the correct answer is A. Choice B, 'To be uniquely discovered,' is incorrect as it does not relate to the composition of a drop of water. Choice C, 'To be set apart,' and Choice D, 'To be surprised,' are also incorrect as they do not convey the meaning of 'composed' as it is used in this paragraph.