What is the meaning of the word 'technical' as it is used in the fourth paragraph?

Correct Answer: A

Rationale: The correct answer is 'A: requiring expert knowledge.' In the context provided, 'technical' refers to articles that demand expert knowledge to understand. The passage mentions that articles published in medical journals can be technical, meaning they are complex and require specialized expertise to comprehend. Choice B, 'incomplete,' is incorrect as 'technical' does not imply incompleteness. Choices C and D, 'foreign' and 'plagiarized,' are also incorrect as they do not align with the context of the passage.

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.

Correct Answer: C

Rationale: The correct summary of the passage is option C. The passage explains how the ECG systematically measures and records the 'wave of excitation' that occurs within the heart in three distinct steps, spreading from the SA node to the AV node. This summary effectively captures the main focus of the passage. Option A is incorrect because it only mentions the detection of electric currents in the body and recognizing abnormalities by medical staff, missing the key information about the 'wave of excitation' and its stages. Option B is incorrect as it focuses solely on the measurement and recording of unique electric currents on the body's surface, neglecting the specific process described in the passage. Option D is also incorrect as it provides a general description of how the ECG measures electric currents without emphasizing the specific stages of the 'wave of excitation' as detailed in the passage.

Correct Answer: B

Rationale: In the context provided, 'emitting' means releasing, specifically referring to the electric currents being released in the body. The passage describes how electric currents are constantly being emitted in the body and can be detected on the body's surface, ultimately recorded by an electrocardiograph. This process is about the release of electric impulses, making 'releasing' the correct interpretation. Choice A, 'Repelling,' implies pushing away, which is not the intended meaning in this context. Choice C, 'Closing,' and Choice D, 'Charging,' do not align with the context of electric currents being emitted.

Correct Answer: D

Rationale: The correct answer is D. The author's primary purpose for writing the essay is to inform the reader about the stages of the water cycle. The essay discusses the various stages of the water cycle, including precipitation, runoff, evaporation, and condensation. Choices A, B, and C are incorrect because the essay focuses on explaining the water cycle stages rather than persuading the reader to conserve water, discussing the effectiveness of runoff, or analyzing different types of runoff.

Correct Answer: A

Rationale: In the context of the immune system, 'enlist' means to call into service. Immune cells recruit other cells to fight infection by producing chemicals that regulate their growth, behavior, and direct new recruits to trouble spots. This process is essential for the immune system's defense mechanism. The other choices are incorrect: 'write down' and 'put across' do not capture the action of mobilizing immune cells, and 'send away' is opposite in meaning to what is happening in the immune response.

Correct Answer: C

Rationale: 'Phased in' means implemented in stages, referring to the gradual implementation of good manufacturing practices. In the provided extract, it mentions that requirements for good manufacturing practices (GMPs) were phased in for small manufacturers through 2010, indicating a gradual implementation process. The other choices, 'stunned into silence,' 'confused,' and 'legalized,' do not accurately reflect the meaning of 'phased in' in the context of the paragraph.

Correct Answer: B

Rationale: In the context of the given extract, 'evolved' means to gradually develop. The systems in the body have evolved over time, indicating a gradual development and adaptation. 'To spread,' 'to revolve,' and 'to shift' do not capture the idea of a gradual development as portrayed in the text, making them incorrect choices.

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.