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    Durian(榴莲) is probably the smelliest fruit in the world, letting out an unusual unpleasant smell which would make anyone bring up. However, nobody was aware of what gave this fruit its unique smell, so a team of researchers from Singapore decided to take a look at its genome (基因组) and find out,

    Durian is well-known throughout Southeast Asia as the king of fruits, mostly because of its awful appearance and smell. However, the origin of this unpleasant smell was unknown, so researchers decided to map the genome of the fruit, and find the gene that controlled it. A group of genes, volatile sulfur compounds (含硫化合物), became very active in the fruit, and they were found responsible for resulting in the unpleasant smell.

    The fruit confuses everyone with a sulfuric smell, like rotten onions and ingredients. The smell lasts long, mostly because the fruit contains more volatile sulfur compounds. Other species usually benefit from two gene copies at most, but durian has four, leading to the striking smell.

    However, this smell might be an advantage for durian in the wild. Although we find it unpleasant, many animals might be attracted by it. If they eat the fruit, then they can easily spread its seeds everywhere, thus contributing to the distribution of the species.

    The mapping of the durian genome also showed some other information on the species. First of all, the fruit has an impressive number of genes, namely 46,000. Also, with the help of these genes, they saw how it evolved, and discovered it was related to the cacao tree. All the other discoveries have been published in the journal Nature Genetics.

    Despite the striking smell, many people actually enjoy eating the fruit. However, not all durian species are edible, and some of them may even cause damage to our health, Even so, the fruit is often imported, significantly contributing to the economy.

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阅读下面的戏剧片段,思考并回答问题。

    在下棋声中,收猪人瞟了一眼画家,大意中走错了一个棋子。

卖猪人:哎,我吃车。

收猪人:(突然按住卖猪人的手)等等!回一步。

卖猪人:咱还兴回棋?

收猪人:(冷冷地)那中,你吃吧!

卖猪人:(意识到)中,中,你回吧,你回吧。

收猪人:(得意地又换另一个棋子)我不走那一步啦。

        [当卖猪人又走下一步棋时]

收猪人:(警告地)你敢动那个子儿,就叫你死!

卖猪人:叫我死?……对,赶快死。干脆,我自杀吧!(摆下那个棋子儿)

收猪人:你不能走那个子儿!

卖猪人:咋?……你不叫我死吗?

收猪人:不兴故意死!

卖猪人:(无奈地)你要是不叫我死,我就先活着。

        「两人继续走棋」

收猪人:发现一步好棋,强调地)咱可不能回啦!将!

卖猪人:(忽然高兴起来)你老弟的棋下得真好。(哭丧着脸恳求地)我那猪拉来过磅吧?

收猪人:(洋洋得意地)你先举举手……

卖猪人:(不解地)举举手?

      [幕后声:“谁的猪跑啦?”」

卖猪人:(向幕内一看)我的猪!我的猪跑啦!(跑下)

        卖猪人内喊:“同志,来帮帮忙!”

        画家跑下

        一阵猪嚎叫声。少顷,画家摊着沾有猪屎的双手上。

        卖猪人跑上,感激地用自己的上衣为画家擦拭手上的猪屎。

卖猪人:(稳住了精神,走近收猪人)我的猪逮住了,拉过来过磅吧?

收猪人:你还没举手呢。

卖猪人:举手?

收猪人:刚才那盘棋你输了,你就得举手投降!

画家:(爆发地)你太过分了!(欲冲向收猪人)

卖猪人:(急拦住画家)你甭生气甭生气。我个小老百姓,人家叫咋着就咋着。不就是举举手吗?(不待画家未置可否,转向收猪人)老弟,我投降我投降……(频频举手)

画家:(极其生气地冲到收猪人面前)我说你这个同志办事也太过分啦!这位老同志来卖猪,你让他等一会儿他就等一会儿,他不愿意和你下棋你非让他和你下棋,闹得他的猪差点跑了。这实在是令人……咱们都是国家工作人员,应当有点职业道德,总还要讲点精神文明吧?

收猪人:精神文明?

画家:你……(激动地)好!精神文明你也不懂,可你百般戏弄一个老实巴交的乡下人。你还有没有良知?

收猪人:良知?

画家:良知就是良心,良心你懂不懂?

收猪人:(皮笑肉不笑地)良心良心,就你要良心?噢!你是个老雷锋啊。(突然把脸一沉)办你的好事去吧!

画家:(更加气愤地)好!这些都不讲,现在咱们去找你的领导,看你在工作时间下棋对不对?

收猪人:我对!

画家:你……

收猎人:咋着咋着?今天我非下棋不可!(故意摔打着棋子儿)我下,我就下!

画家:(怒不可遏)你不能下!(掀翻棋盘)

卖猪人:(忽然意识到什么,上前将画家摔了一个趔趄)唉!

画家:(不可理解地)你?

        卖猪人与画家对视片刻

卖猪人:(痛心疾首地)是我卖猪呀!我卖猪我还不急哩,你是急啥哩?

画家:(完全糊涂了)我……

        收猪人强硬地摔着棋子儿

        卖猪人在砰砰的棋子儿声中走近收猪人,他思索片刻,忙般勤地拾起掉在地上的棋子儿,轻轻地放在棋盘上,又诚惶诚恐地乞求收猪人……