问题 解答题

现在一些商店里流行一种生态球,该球密封,内装有水,两三条小鱼或小虾自由地在水中游动着,底部有珊瑚、沙子,并长有一些绿绿的水藻.

(1)这个生态球可以看作是一个生态系统吗?写出原因.

(2)这个生态球应放在什么地方?

(3)小鱼和水藻能共同生存的原因是什么?

答案

(1)、一个完整的生态系统包括生物部分和非生物部分,非生物成分包括阳光、空气、水和土壤等,它们为生物提供能量、营养和生存空间;而生物部分由生产者、消费者和分解者组成.生产者主要指绿色植物,能够通过光合作用制造有机物,为自身和生物圈中的其他生物提供物质和能量,植物体的光合作用的原料是二氧化碳和水,消费者主要指各种动物,在促进生物圈中的物质循环起重要作用,分解者是指,细菌和真菌等营腐生生活的微生物,它们能将动植物残体中的有机物分解成无机物归还无机环境,促进了物质的循环.在一般情况下,生态系统中各种生物的数量和所占的比例总是维持在相对稳定的,即生态平衡;这说明生态系统具有一定的自动调节能力,但这种自动调节能力有一定限度,如果外界干扰超过了这个限度,生态系统就会遭到破坏.

(2)如果把这个生态球放在黑暗中,里面的生物不能存活.没有阳光,水藻不能进行光合作用,不能产生氧气,小鱼、小虾就会死亡;小鱼、小虾死亡后不能再产生二氧化碳和无机盐,水藻也会死亡.所以,这个生态球应放在有充足阳光照射的地方.

(3)有资料可知,绿色植物通过光合作用制造的有机物是生物的食物和能量来源,动物直接或间接的以植物为食属于消费者,所以,小鱼有水藻提供的氧气与食物;水藻利用小鱼提够的光合作用的所需原料.

故答案为:(1)可以看作是一个生态系统.因为它大体上符合生态系统的特征,具有生态系统的基本组成,具有一定的自动调节能力;(2)有充足阳光照射的地方;

(3)小鱼有水藻提供的氧气与食物,水藻利用小鱼提够的光合作用的所需原料.

单项选择题
阅读理解

阅读理解

    When you were looking for a reliable, honest auto mechanic, how did you find him?Before you went

into that restaurant you recently tried, how did you know that it served great food?If you are like most

people on the planet, you want to lower your risk of a big ugly surprise so you asked people you trust to

refer to a business they trust.Marketers call this friendtofriend recognition of a business "wordofmouth"

advertising.

     When you do a great job for your customer or a bad job, people are going to talk about your

business.Unfortunately, because we humans seem to feel negative emotions more intensively than positive

ones, we're more likely to tell more of our friends about bad experiences with a business than positive

ones.Understand this:Customers believe their own experience.You can't make them believe that your

company is wonderful when they felt they were treated badly.

     So, to get positive wordofmouth going for your business in this servicebased economy, you've got to

do a really outstanding job for everyone, exactly.

     And when you do, you build a great reputation.That takes time.But it forms a close link with your

customers in a way that no advertising and no promotional coupon (优惠券) ever could.

     The good news is that because there are so many different businesses chasing after your customers'

money, people want to know whom they can trust.So people are going to be talking about you.Create a

free sales force for your business-an army of delightedcustomers who tell everyone that they know how

good your company is to do business with.That's a great antidote (解毒剂) to defectionitis.

1. What is the main topic of this passage?

A. A good name will bring you money.

B. A person should rely on his friends for business.

C. Advertising can make customers believe it's wonderful.

D. A company can rely on its associates to survive.

2. According to the passage, whether we go to a place or not depends on________.

A. business fame

B. media assistance

C. particular recognition

D. associates'recommendation

3. When you do an outstanding job in service, you will surely________.

A. make more money than you expect

B. have a mutual understanding with your customers

C. build a great reputation immediately

D. earn your fame as well as advertise for your company

4. The underlined word "defectionitis" probably means________.

A. service imperfection

B. customers' distrust

C. customers'protection

D. service advertisement