Questions 1-11 are based on the following passage.
Adapted from Abi Berger, ”Magnetic Resonance Imaging,”©2002 by Abi berger.
1.Which choice best reflects the author’s point of view regarding magnetic resonance imaging (MRI)?
A) It is the most important tool used by scientists to aid in the diagnosis of particular diseases.
B) It is a valuable and effective technique but should be used sparingly in order to prevent possible damage to the body.
C) It is a breakthrough technology that will revolutionize the treatment of particular ailments.
D) It is a useful tool in disease diagnosis,although specialized training is required to accurately interpret MRI images.
2.Which choice provides the best evidence for the answer to the precious question?
A) lines 17-21 (“The strength...applied”)
B) lines 30-34 (“Multiple...off ”)
C) lines 42-47 (“Different...it”)
D) lines 48-54 (“Most...answer”)
3.It can reasonably be inferred from the passage that, like a bar magnet, the nucleus of a hydrogen atom
A) spins in a counter-clockwise direction.
B) is responsive to external magnetism.
C) attracts metallic substances.
D) is surrounded by electrons.
4.Over the course of the passage, the main focus shifts from
A) an explanation of how magnetic resonance imaging (MRI) works to a discussion of MRI’s practical advantages.
B) a story about the origin of magnetic resonance imaging (MRI) to a discussion of alternative imaging methods used by scientists.
C) an explanation of tissue relaxation rates to a summary of the magnetic properties of hydrogen protons.
D) an introduction about the properties of radiofrequency waves to a criticism of the health risks of x-ray devices.
5.The “planet earth” image in line 6-7 mainly serves to
A) highlight an unlikely parallel between the fields of biology and astronomy.
B) inject a note of humor into an otherwise serious explanation of magnetic resonance imaging.
C) create a pun centered on the idea that hydrogen is necessary for life on this planet.
D) communicate a complex scientific idea using a more familiar concept.
6.It can reasonably inferred from the passage that electromagnetic waves in the radio frequency range
A) do not create long-lasting effects on the human body.
B) only create magnetic fields in tissues with high water content.
C) are stronger than waves in the x-ray range.
D) always travel in the same direction.
7.Which choices provides the best evidence for the answer to the previous question?
A) lines 22-24 (“When...emitted”)
B) lines 28-29 (“The...up”)
C) lines 34-39 (“The time...state”)
D) lines 55-59 (“There...through”)
8.As used in line 49, "sensitive" most nearly means
A) appreciative
B) unstable
C) discerning
D) observant
9.The data in the table support the author’s point that
A) pulse relaxation times can be used to identify different tissues in the body.
B) magnetic resonance imaging is safer than other imaging techniques.
C) infections and tumors look similar using magnetic resonance imaging.
D) hydrogen protons behave like a small bar magnet.
10.According to the table,which tissue is the first to return to its original magnetic vector resting state?
A) Water/CSF
B) Liver
C) Fat
D) Tendon
11.It can reasonably be inferred from the table that
A) some tissues display axial spin relaxation times are much longer than their magnetic vector relaxation times.
B) it generally takes longer for the magnetic vector to return to its resting state than the axial spin.
C) it often takes twice as long for the axial spin to return to its resting state than the magnetic vector.
D) it always takes at least three times as long for the magnetic vector to return to its resting state than the axial spin.
