题干

科研人员对某岛屿连续两年中社鼠种群数量和性比(♀:♂)进行研究,结果如图,据图分析正确的是(    )

A:决定该岛屿社鼠种群数量的直接因素有出生率、死亡率、迁入率和迁出率

B:可以用样方法获取该岛屿社鼠种群数量的变化数据

C:社鼠雌性个体在秋冬季节环境中生存能力低于雄性个体

D:社鼠种群密度较低时,较高性比(♀:♂)有利于种群密度恢复

上一题 下一题 0.0难度 选择题 更新时间:2019-06-11 10:20:43

答案(点此获取答案解析)

D

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     Do you know what Oscar is? When did it start? Maybe you can find the background of the awards in the following passage.

The awards started in 1929. Their full title is “The Academy of Motion Picture Arts and Sciences Awards”. The Academy is a group of people who have worked in the film industry for many years. They decide who will receive the awards. The awards are often referred to as the “Oscar”. This is a nick name given to the awards by a lady called Margaret Herrick. She was once the director of the Academy and she once said that the little gold statue reminded her of her uncle Oscar!

    The Oscar is always an exciting event. Each year, at least one unusual thing happens. When the Italian actor and director Roberto Benigni won an Oscar for best foreign film, he danced on stage! When Gwyneth Paltrow,the star of Shakespeare in Love won the Oscar for best actress, she could not make her acceptance speech because she was crying so much with happiness!

    In 1987, Roberto Benigni won the award for best director for a film about the last emperor of China. Since then, Chinese film and actors have started to make an impact at the awards. Crouching Tiger, Hidden Dragon was a huge success and it won the award for best foreign language film in 2001.It also won several technical awards for its amazing “flying” people. We expect to see more awards for Chinese film in the near future.

    It's time for the Oscar again. Once more, the stars will dress up in their finest and go to Kodar Theater. There, they will find out who have won the awards for best actor, best actress and best director. Millions of people watch the awards every year to find out who the winners are. Some people watch it to see the stars crying and laughing as they receive their awards.