问题 选择题

下列各生物分类单位所包含的生物中,蛋白质分子相似程度最高的应是

A.种

B.目

C.门

D.纲

答案

答案:A

分析:此题考查的知识点是生物的分类等级的特点.解答时可以从分类单位以及分类等级的特点方面来切入.

解:生物分类单位由大到小是界、门、纲、目、科、属、种.界是最大的分类单位,最基本的分类单位是种.分类单位越大,生物的相似程度越少,共同特征就越少,包含的生物种类就越多,生物的亲缘关系就越远;分类单位越小,生物的相似程度越多,共同特征就越多,包含的生物种类就越少,生物的亲缘关系就越近.如人种:黄种人、白种人、黑种人,他们相似程度多,亲缘关系就近.

故选:A.

阅读理解

Commencement (毕业典礼) is a time for idealism.

But economic reality is cruel everywhere; especially for new graduate. They have been told repeatedly that a college degree is an open sesame(芝麻) to the global economy. But that’s not necessarily so, according to new research by two economists at he Massachusetts Institute of Technology, Frank Levy and Peter Temin.

It is true that people with college degrees make more money than people without degrees. The gap has narrowed somewhat in recent years, which is disturbing. But the earning power of college graduates still far outpaces that of less-educated workers.

The bad news, though, is that a college degree does not ensure a bigger share of the economics pie for many graduates. In recent decades Mr. Levy and Mr. Temin show, only college-educated women have seen their income grow in line with economy wide gains in productivity. The earnings of male college graduates have failed to keep pace with productivity gains.

Instead, a huge share of productivity growth, which expands the nation’s income, is going to Americans on the top of the income scale. In 2005, the latest year with available data, the top of 1 percent of Americans---whose average annual income was $ 1.1 million--- took in 21.8 percent of the nation’s income, their largest share since 1929.

Administration officials, and other politicians and economists, often, believe that income inequality, reflects an education gap. But Mr. Levy and Mr. Temin show that in the case of men, the average bachelor’s degree is not enough to catch the rising tide of the global economy.

They argue that the real reason that inequality is worsening is the lack of strong policies that broadly distribute economic gains. In the past, for example, a more progressive income tax and unions promote equality. Positive measures have been eroding and new ones have not yet emerged, making the income gap even greater.

Mr. Levy and Mr. Temin conclude that only a new government policy can restore general prosperity. That’s a challenge to the nation’s leader and today’s graduates. America needs them to contribute to the development of the nation in global economy.

小题1:The passage is mainly about that _______.

A.there is a big income gap between female and male college graduates in America.

B.college graduates find it hard to find an ideal job after graduation in America.

C.research shows that American government should take measures to ensure income equality for college graduates

D.college degrees are losing value in America.小题2:What is the main idea of paragraph 5?

A.The whole nation has enjoyed a big income growth with the growth of productivity.

B.Much of the total income in America has been gained by a few very rich people.

C.A small part of people in America have income increase.

D.Upper class Americans contribute most to productivity growth.小题3:The underlined word “eroding” in paragraph 7 probably means _______.

A.being gradually destroyed by wind or rain

B.gradually reducing power

C.gradually disappearing

D.gradually not suitable小题4:We can infer from the passage that _______.

A.female college graduates have higher income than male ones.

B.female college graduates have benefited from some governmental measures to ensure their income growth.

C.income tax can grantee income equality.

D.new measures and policies have been taken to promote income equality.小题5:From the passage, some economists believe that the worsening income inequality is caused by ______.

A.lower college degree of college graduates

B.lack of proper governmental policies

C.gender discrimination

D.underdevelopment of economy and productivity.

单项选择题