问题 读图填空题

研究人员测定了香梨果实从形成到成熟及采收后某些激素含量的动态变化,其结果如下图所示,请分析并回答:

(1)在香梨果实发育初期(花后15天左右)达到高峰,且在果实迅速膨大期间(花后60天左右)含量比值加大的两种激素是______________,在此过程中__________(填激素名称)的作用也是不可缺少的,说明果实正常发育是_______________的结果。

(2)香梨果实采收后30天才进入完全成熟阶段,在此过程中乙烯含量的变化说明其主要作用是_________。

(3)采收后___________的骤减是果实成熟的必要条件,脱落酸积累可能触发了果实的衰老过程,________________含量再次升高,可能促使衰老阶段乙烯的大量合成,因此在果实成熟衰老后期调节_________至较低水平将是延缓香梨果实衰老的关键。

答案

(1)赤霉素和脱落酸     生长素     多种激素共同作用

(2)促进果实成熟

(3)赤霉素     生长素     脱落酸和生长素

单项选择题
阅读理解

AIDS’ Threat to Asia Grows

NEW DELHI----Just a few years ago, Mala was a typical middle-class Indian housewife. She cooked, cleaned and looked after her two small children.

Last year, her life took a tragic turn. Her husband died of AIDS; she was found out HIV-positive and her mother-in-law took her children away from her, saying they would get the disease. “When friends dropped for a visit, she would introduce me, saying, ‘She is my son’s widow. She has AIDS,’” said Mala. AIDS is now described as “explosive(炸药)” around the world. A study of a hospital in the port city of Durban in South Africa, where the world’s biggest and Africa’s second AIDS conference opened last Sunday, found that almost half the beds in medical wards (病房) were occupied by AIDS patients.

South Africa has one of the world’s fastest growing HIV infections, with 1,700 people infected daily, adding to the 4.3 million, or 10 percent of its population, living with HIV. Until now, Asia has been more successful in holding the AIDS virus than Africa, where the disease has killed about 12 million people.

AIDS is now threatening to surround many of Asia’s poverty-stricken countries. Countries in Asia, such as Cambodia, and Thailand, have HIV infection speeds over 1 percent. But the low speeds hide huge numbers of infected people, because of the population base.

In India, for example, 3.7 million are infected, more than in any other country except South Africa. In China, an estimated 860,000 people (the actual number may be a little larger), mainly drug users, live with HIV/AIDS. Gordon Alexander, a senior advisor for UN AIDS in India, estimates that the number hit by AIDS in Asia will climb about eight million over the next five years from about six million.

In many Asian countries, the battle against HIV is a social and cultural one against public discussion of sexual health put a nationwide media campaign into action to limit the speed of HIV through unsafe sex. Brenton Wong, an official for Singapore’s Action for AIDS, says the actual HIV incidence in the city state of 3.9 million people is at least eight times higher than official data. “Shame and deny is still very, very common so people are afraid to get tested and many times won’t even tell their families if they test positive,” said Wong.

小题1:We can conclude from the underlined sentence in the last paragraph that ______.

A.The official data always tell lies and cheat people to hide the truth.

B.3.9 million people in Singapore suffered from AIDS.

C.Singapore has a population of 3.9 million

D.The number of people infected with HIV is at least eight times larger than that of the AIDS patients in Singapore.小题2:It is judged that there are ______ people hit by AIDS in Asia or so.

A.4.3 million

B.6 million

C.8 million

D.3.7 million小题3:According to the passage, the main reasons that AIDS spread in Asia is through_______. 

A. blood

B.unsafe sex

C.love

D.drugs小题4:Which of the following statements is not right?     

A.The battle against Aids in many Asian countries is against their culture and

social customs.

B.Though the HIV infection in Asia develops with low speed, the infected number

is still quite large compared to other continents.

C.India has the second largest number of HIV infected people.

D.Aids might affect the poverty-stricken countries more severely.