[填空题]Scientists use ______ to test whether their genetic modification of a plant is successful.

[单项选择]Researchers disagree whether the "use it or lose it" philosophy holds for cognitive aging, but there is one evidence that keeping mentally active can slow age-related declines.
At Pennsylvania State University, Sherry Willis and her husband, K. Warner Schaie, have studied 5000 people, some since 1956. People lucky enough to avoid chronic diseases may also fare better in intellectual function, they find, perhaps because chronic diseases can restrict lifestyle and reduce mental stimulation. Similarly, those lucky enough to be relatively affluent also fare better, perhaps because money can buy intellectually stimulating things like travel.
Education helps, too, researchers say because of instills the conviction that you can always learn something new. The Schaie-Willis team also has some other observations. Being in a stable marriage with a stimulating spouse, they say, helps maintain intellectual vigor.
Flexibility counts too. People who stay mentally vibrant are often tho
A. the role mental stimulation in preventing mental aging,
B. gradual loss of mental skills with normal aging.
C. the relationship between mental function and spatial skills.
D. effective ways to keep intellectual vigor.

[简答题]According to scientists, we use only 10 persent of our brain.

[单项选择]B Scientists have found a new use for children’s imaginations - to make stomachaches go away. The BBC reports a new study that shows：“Children can be taught to use their imaginations to deal with stomachaches.” This may be very good news for parents who need a quick cure for their sick children. Any mother or father understands：the stomach problem is one of the most frequent things their children complain about. Around twenty percent of children suffer from stomachaches that doctors cannot find a reason for. This new research is especially good for kids with active imaginations.Researchers found that the more creative the child is, the better he or she is at imagining the pain away. The researchers used a relaxing CD with children. A voice guided them them through different fantasy situations. One of these was pretending to be floating on a cloud. Thirty children took part in the tests. Half of them used the “guided imagery”method, and the other half received normal
A. Kids who like listening to music.
B. Kids who are good at remembering things.
C. The independent kids.
D. Kids with active imaginations.

[单项选择]Scientists have long bickered over whether hypocrisy is driven by emotion or by reason. The role of emotion in moral judgments has upended the Enlightenment notion that our ethical sense is based on high-minded philosophy and cognition.
In a new study that will not exactly restore your faith in human nature, psychologists David DeSteno and Piercarlo Valdesolo of Northeastern University instructed 94 people to assign themselves and a stranger one of two tasks, an easy one, looking for hidden images in a photo, or a hard one, solving math and logic problems. The participants could make the assignments themselves, or have a computer do it randomly. Then everyone was asked, how fairly did you act, from "extremely unfairly" (1) to "extremely fairly" (7). Next they watched someone else make the assignments, and judged that person’s ethics.
Selflessness was a virtual no-show. 87 out of 94 people opted for the easy task and gave the next guy the onerous one. Hypocrisy, however, showe
A. emotion.
B. reason.
C. hypocrisy.
D. both emotion and reason.

[单项选择]Scientists use observation and experimentation to examine a specific concept （） existing theories and principles.
A. in the light of
B. in view of
C. as to
D. in the interest of