题干

“地球生态超载日”是指到一年中一个特定日期为止,人类对自然资源的消耗已超过地球在这一年可以产出的资源总量。下图为部分年份地球生态超载日变化图。读图,完成下列各题。

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同类题1

阅读下面的说明文,完成下列小题。

奇特的年轮

       ①人们所熟知的年轮,是树木的年轮。一棵树被锯倒了,数一数树墩上有多少圈条纹,人们就知道这棵树有多大年龄了。另外,树木的年轮里,还储存着当地的气候、地震、火山爆发和水灾旱灾等丰富的自然信息。因此,科学家十分重视从树木的年轮里获取蕴藏着的科学信息资料。

       ②植物中不仅树木有年轮,水仙花也有年轮,它的年轮在它的“蒜头”上,有一个年轮的,开花期短;有三个年轮的,开花期长。因此,有经验的育花者,往往选取年轮多的水仙头,以便使花期长些。

       ③不仅植物有年轮,动物亦有年轮。鲤鱼等鱼类的年轮是其鳞片上的宽窄分界的条纹。令人不解的是,并非所有的鱼的年轮都在鳞片上,大马哈鱼的年轮在它们的背鳍上,大、小黄鱼的年轮却在它们的耳石上。

       ④牛、羊的年轮在它们的犄角上,所以又称为“角轮”。龟、鳖的年轮在它们的背甲上。蚌、贝和螺的年轮在它们的壳上。

       ⑤腔肠动物珊瑚虫的年轮是它们表壁上有粗细之分的规则形条纹。珊瑚虫不仅有它们的年轮,而且还有它们的“日轮”。一年为365日,那么它们便在自己的体壁上划下365条环纹。

       ⑥兔子和黄鼠狼这样的动物也有年轮,年轮在它们的骨头上,不过,要借助显微镜才能观察到。

       ⑦有些鸟也有年轮:据说,美国科罗拉多州的一位山地生物实验室工作人员捉住一只熊蜂鸟,发现近爪处腿皮上有环圈,根据环圈判断,这只鸟已有11岁了,从而否定了一般认为熊蜂鸟的寿命只有8年的说法。

       ⑧日本科学家最先发现人也有年轮,是在人的头颅里面,通过声波可以检测出一个人的实际年龄。如果检测器的声波频率与被检测人的实际年龄相符,人体便会做出反应,从而在荧屏上显示出来。目前,这一先进的科学技术已应用于实际生活中,如用它来检测大型运动会参赛人员的实际年龄,或是应用到刑事案件的侦破中,用以检测涉嫌人员或罪犯的实际年龄,从而为破案提供重要的线索和有力的证据。

       ⑨按理说,一切生物都应该有它们各自的年龄,只不过是有的已经被发现,更多的没有被发现罢了。科学家们正努力探索生物年轮的奥秘,以便有更多的发现,进而造福于人类。

同类题4

根据短文理解,选择正确答案。

    As the new semester begins, millions of college students across the country are trying hard to remember how best to write a paper or, more likely, how best to delay that paper.

    Procrastination is the thief of time and a lot of students suffer form it. They can spend whole days in the library doing nothing but staring into space, eating snacks, surfing the Internet, watching videos and looking at other students sitting around them, who, most likely are doing nothing either.

    Paralyzed (使失去活力) by their habit to procrastinate, they write micro blogs about their fears, asking their online friends if they sometimes have the same issue. But this does nothing to break the spell (魔咒).

    According to a recent report, 95 percent of us procrastinate at some point and 20 percent of the world's population are always procrastinating. The figures are disappointing. Procrastinators are less wealthy, less healthy and less happy than those who don't delay. Procrastinators like to find excuses to justify their behavior, but BBC columnist Rowan Pelling says they are all wrong.

    Many procrastinators tell themselves they are perfectionists who work best under pressure. Pelling says this is non sense, as work done at the last minute is more likely to have mistakes than work done on time. The behavior of procrastinators often makes them feel ashamed, inconveniences others and annoys loved ones.

    Pelling also points out that procrastination feels particularly delinquent(过失的) in a society that thinks of speedy action as admirable, and, at times, even as a moral good.

    Fortunately, social scientists have thrown their weight behind efforts to understand this behavioral mistake and offer strategies to control it. Piers Steel, a Canadian social scientist and author of The Procrastination Equation, believes human is “designed” to procrastinate. Nevertheless, he suggests a couple of good ways to get through the task at hand.