问题 单项选择题

下列哪项不是细胞衰老的特征()

A.细胞内水分减少

B.细胞呼吸速率减慢

C.细胞内色素积累较多

D.细胞膜通透性不变,物质运输功能增强

答案

参考答案:D

解析:细胞衰老有以下特征:细胞内水分减少,呼吸速率减慢,色素积累较多,细胞膜通透性改变,物质运输功能下降,故D错。考点:本题考查细胞衰老相关知识,意在考查考生能理解所学知识的要点,把握知识间的内在联系,形成知识的网络结构能力。

阅读理解

阅读理解。

     A seventeen-year-old boy from the northeastern state of Massachusetts has won the top prize in the Intel

Science Talent Search. The competition is the oldest program in the United States that honors the science

projects of high school students. The Intel Science Talent Search is 63 years old this year.

     The winners receive a new computer and money for a college education. This year 1 652 students from

46 states entered projects for the competition. Their research involved nearly every area of science, including

chemistry, medicine, physics, mathematics, engineering, computer science and social science.

     Forty students were invited to Washington, D. C. for the final judging. A group of well-known scientists

judged them on their research abilities, critical thinking skills and creativity. The judges also questioned the

students about scientific problems before deciding on the winners.

     The top winner is Herbert Mason Hedberg of North Attleboro, Massachusetts. The second place winner

is Boris Alexeev of Athens, Georgia and the third place winner is Ryna Karnik of Aloha, Oregon. Herbert

received 100 000 dollars for his college education. He developed a faster, more effective method to tell if a

person has cancer. He explored a way to separate telomerase, an enzyme (酶) found in most cancer cells. His

findings have helped advance research into ways of stopping cancer cells from growing. Herbert said he started

the project after watching his grandmother struggle against cancer. He plans to be a doctor and continue doing,

medical research.

     Andrew Yeager of the University of Pittsburgh Medical Center was chairman of the judges for the Intel

Science Talent Search this year. He said the competition was an excellent way to discover future leaders in

science and technology. Past competition winners have gone on to receive many of the world's highest honors

for science and mathematics.

1. Herbert's way is more effective because _____.

A. it can kill cancer cells faster

B. it helps to free humans from cancer

C. it can stop cancer cells from growing

D. it can tell faster if a person is a cancer sufferer

2. We can learn from the passage that _____.

A. the final judging of the competition took place in the state of Massachusetts

B. less than three percent of the competitors entered the final part of the competition

C. critical thinking and creativity are more important than research abilities

D. the scientists judging this year's competition all work for Intel Corporation

3. What would be the best title for the passage?

A. Intel Science Talent Search

B. How to Discover Future Scientists

C. Intel Science Talent Search Winners

D. A Very Famous Competition

单项选择题