Question

【題目】 A study has shown that severe stress lasting weeks or months can damage cell communications in the brain’s memory areas. Recently, researchers from University of California, Irvine, have provided the first evidence that short-term stress lasting for a few hours has the same effect.

“Stress does exist in our lives and cannot be avoided,” said Dr. Baram, leader of the UC Irvine School. “Our findings can play an important role in the present development of medicine that might prevent these undesirable effects and offer understanding of why some people are forgetful or have difficulty keeping the memories.”

In their study, Baram and her UC Irvine colleagues identified a novel process in which stress caused these effects. They found that, severe stress activated(激活) Corticotropin Releasing Hormones(CRH), which prevented the brain from keeping memory.

Memory takes place at synapses, where there are connections through which brain cells communicate. These synapses lie on dendritic spines(神經(jīng)元). In rat and mouse studies, Baram’s group saw that the release(釋放) of CRH in the brain’s primary memory center led to the rapid breakup of these dendritic spines, which in turn limited the ability of synapses to collect and store memories.

In addition, the researchers reproduced the effects of stress on dendritic spines by keeping low levels of CRH, and watching how the spines ruptured over minutes. “Fortunately, once we removed the CRH, the spines seemed to grow back again, ” Baram said. “And this study can play a role in the creation of treatments to address stress-related memory loss.”

【1】According to the text, short-term stress can lead to ________.

A.memory lossB.cell decrease

C.head damageD.thought disorder

【2】The underlined word “ruptured” in Paragraph 5 is closest in meaning to ________.

A.came into beingB.built up

C.broke apartD.died away

【3】What is the author’s purpose of writing the text?

A.To discuss the main stages of stress.

B.To show the primary cause of stress.

C.To introduce a new finding about stress.

D.To promote an effective treatment for stress.

Answer 1

【答案】

【1】A

【2】C

【3】C

【解析】

這是一篇說(shuō)明文。主要介紹了科學(xué)家關(guān)于壓力對(duì)人的記憶的影響的研究，長(zhǎng)期的壓力會(huì)導(dǎo)致記憶損失，但最新的研究發(fā)現(xiàn)，短期的壓力也會(huì)對(duì)記憶造成損害，引起記憶的損失并分析了原因。

【1】細(xì)節(jié)理解題。根據(jù)第一段中A study has shown that severe stress lasting weeks or months can damage cell communications in the brain memory areas和that short-term stress lasting for a few hours has the same effect.可知，長(zhǎng)期的壓力會(huì)損害人的記憶，短期的壓力也有同樣的結(jié)果。故選A項(xiàng)。

【2】詞義猜測(cè)題。根據(jù)第四段中In rat and mouse studies, Baram’s group saw that the release(釋放) of CRH in the brain’s primary memory center led to the rapid breakup of these dendritic spines, which in turn limited the ability of synapses to collect and store memories.可知，在老鼠的實(shí)驗(yàn)中，釋放CRH會(huì)導(dǎo)致樹(shù)突棘的迅速分裂，進(jìn)而限制了突觸收集和儲(chǔ)存記憶的能力；再根據(jù)最后一段中In addition, the researchers reproduced the effects of stress on dendritic spines by keeping low levels of CRH, and watching how the spines ruptured over minutes.可知，在第二個(gè)實(shí)驗(yàn)中科學(xué)家通過(guò)保持少量CRH，來(lái)觀測(cè)神經(jīng)元的________情況。故畫(huà)線部分的意思和break up(分解)相近。C項(xiàng)broke apart（分解）與此相近。故選C項(xiàng)。

【3】推理判斷題。根據(jù)文章第一段的A study has shown that severe stress lasting weeks or months can damage cell communications in the brain’s memory areas. Recently, researchers from University of California, Irvine, have provided the first evidence that short-term stress lasting for a few hours has the same effect.可知，一項(xiàng)研究表明，持續(xù)數(shù)周或數(shù)月的嚴(yán)重壓力會(huì)損害大腦記憶區(qū)域的細(xì)胞通訊。最近，加州大學(xué)歐文分校的研究人員首次證明，持續(xù)數(shù)小時(shí)的短期壓力也有同樣的效果。所以作者寫(xiě)作的主要目的是介紹一項(xiàng)關(guān)于壓力會(huì)對(duì)記憶力造成損害的發(fā)現(xiàn)。C項(xiàng)To introduce a new finding about stress.(為了介紹一項(xiàng)關(guān)于壓力的新發(fā)現(xiàn))是作者的寫(xiě)作目的。故選C項(xiàng)。