问题 选择题

在“草→鼠→鹰”这个食物链中,若将鹰杀绝,那么鼠的数量将会(  )

A.保持原有状态

B.缓慢下降

C.迅速上升

D.先上升后下降

答案

生态系统的结构包括生产者、消费者、分解者、非生物的物质和能量,其复杂程度决定了生态系统维持平衡能力的大小,即生态系统自我调节能力的大小,因为生态系统的结构越复杂,生态系统能量流动和物质循环的途径就越多,其抵抗外界干扰的能力就越强,也就是说其调节能力就越大;反之,结构越简单,生态系统的调节能力就越小,维持平衡的能力就越弱.此生态系统的生产者是草,消费者是鼠、鹰,如果捕杀了全部鹰导致鼠因没有天敌而大量繁殖,所以鼠的数量迅速上升,但草由于鼠的增加而草被吃光,所以鼠的数量将会将会先上升后下降.

故选:D.

阅读理解

Fannie Cratty wasn’t really my aunt. I only referred to her as “My Aunt Fannie” because the name always made my father laugh and gave my mother cause to look angrily at both of us---at me for being disrespectful of my elder and at my father for encouraging my bad behavior.

As a young woman, my mother had worked in the kitchen of a large Victorian farmhouse owned by Fannie Cratty. During those years my mother helped Aunt Fannie make the best blueberry jam ever tasted by anyone in Glenfield. Aunt Fannie was well known for her jam and for never sharing the recipe with another living soul. Even though my mother knew the recipe by heart, as long as Aunt Fannie was alive (and she lived to be ninety-six!), she never made the jam without Ms. Cratty in our kitchen to direct the process and preserve the secret. 

Each August, when blueberry season would roll around, my mother would prepare me for Aunt Fannie’s visit. It was vital that I should be on my best behavior. After all, the woman was old, wealthy, very strict with children. Whenever she was at the house, I didn’t need to be reminded to guard my thoughts and watch my tongue. 

One year, after I had been particularly helpful with the jam process, Aunt Fannie gave me a quarter(25分硬币) and then made me promise that I would never spend it. “Hold onto this quarter,” she said, “and someday you will be rich. I still have my very first quarter, given to me by my grandfather.” It had obviously worked for her. So, I kept the 1938-quarter into a small box, put it in my dresser drawer, and waited to become rich. 

I now have the blueberry jam recipe and the quarter from Aunt Fannie. In people’s eye Aunt Fannie’s success was due to that secret recipe. But to me, it was just a common recipe. Neither has significantly contributed to my wealth, but I keep them as reminders to hold onto the valuable things in life. Money can make you feel rich for a while, but it is the relationships and the memories of time spent with friends and family that truly leave you wealthy. And that is a fortune that anyone can build.

小题1:Paragraph 2 implies that my mother    .

A.used to forget the secret blueberry jam recipe

B.wanted to show off her excellent cooking skills

C.was unable to make the jam without Aunt Fannie’s direction

D.tried to convince Aunt Fannie that she would keep the secret小题2:According to Paragraph 4, the author believed that Aunt Fanni was rich because    .

A.she had kept her first quarter

B.she had never wasted money

C.she had worked very hard

D.she had kept her promise小题3:The author thinks that we can feel wealthy if we    .

A.share our wealth with others

B.have good fortune and money

C.know the secret of a jam recipe

D.own lasting love and friendship小题4:Which would be the best title for this passage?

A.An old quarter

B.Valuable Things

C.Blueberry Jam Recipe

D.Memories of old time

单项选择题