问题 选择题

有关遗传与变异的说法,正确的是[ ]

A.基因型为Dd的豌豆,产生雌雄两种配子的数量比接近1:1

B.自由组合定律的实质是所有等位基因分离,非等位基因自由组合

C.孟德尔成功的原因是从研究豌豆的全部相对性状综合分析入手

D.DNA中脱氧核苷酸的种类和数量发生改变,不一定引起染色体变异

答案

答案:D

名词解释
阅读理解

My dream ended when I was born. Although I never knew it then, I just held on to something that would never come to pass. Dreams really do exist. But in the morning when you wake up, they are remembered just as a dream. That is what happened to me.

I always had the dream to dance like a beautiful ballerina(芭蕾舞女演员)turning around and around and hearing people applaud for me. When I was young, I would turn around and around in the fields of wildflowers that grew in my backyard. 

Reality woke me up when I heard someone saying, "I don't know why you bother trying to dance. Ballerinas are pretty and slender(苗条) girls. Besides, you don't have the talent to even be a ballerina." I remember how those words hurt every feeling in my body. I fell to the ground and wept for hours. 

I enjoyed hanging out by the water. I would sit there for hours and stare at my reflection(倒影). There I was, looking nothing like a pretty ballerina dancer. Reflections don't lie. Once the waves would come, my reflection was washed away just like my dream to dance.

As I grew older, I began to realize that the reason my dream was even born was because it was something that was inside of me. The dream I had was never nurtured(培育) and cared for, so it slowly died. It's not that I wanted it to die, but I allowed it to die the day I started listening to the words, "You can't do it." When I finally woke up from many years of dreaming, I realized that you can't only settle for dancing in the wildflowers, you have to move on to the platform.

小题1: Which of the following can serve as the best title for the passage?

A.Care for your dream

B.Dream and reality

C.Nothing is impossible

D.Efforts to be a ballerina will pay 小题2:The author didn’t realize her dream of being a ballerina mainly because_______.

A.she was bored of dancing and performing

B.she had lack of self-respect

C.her health conditions allowed her dream to die

D.she was deeply affected by others easily小题3:From the passage, it can be inferred that _________.

A.the author was once a pretty and slender girl with wonderful dream.

B.we should dare to give up our dream facing much pressure and difficulty

C.if you stick to your dream and never say die, you will enjoy a bright life

D.You should necer give up.小题4:What is the main purpose of writing the passage?

A.to complain

B.to praise

C.to warn

D.to criticize小题5:The underlined expression “settle for” in the last paragraph means_________.

A.turn down

B.take up

C.give up

D.settle down