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问题 单项选择题

完成寄生虫的生活史均需中间宿主的是

A．日本血吸虫、疟原虫、似蚓蛔线虫
B．广州管圆线虫、华支睾吸虫、疟原虫
C．十二指肠钩虫、卫氏并殖吸虫、链状带绦虫
D．旋毛形线虫、蠕形住肠线虫、隐孢子虫
E．华支睾吸虫、溶组织内阿米巴、班氏丝虫

答案

参考答案：C

解析：有些寄生虫完成生活史需要中间宿主或吸血昆虫，即虫体只有在中间宿主或吸血昆虫体内发育至感染阶段后，才能感染人体。十二指肠钩虫完成生活史必须由中间宿主蚊子完成。链状带绦虫中间宿主是猪，卫氏并殖吸虫第一中伺宿主为淡水螺类蜷科(Thiaridae)和黑贝科(Pleuroceridae)中的某些螺，第二中间宿主为甲壳纲的淡水生物。

选择题

竞争中必须遵守的基本准则是[ ]

A．诚实和信任

B．道德和法律

C．合作与共享

D．宽容与尊重
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听力题

根据短文内容及首字母提示,填写所缺单词

In the 1930s, Dan West was farming in Spain.  It was wartime, and people were starving (挨饿). An i小题1: hit him

as he handed out cups of milk to children. “These children don’t need a cup.  They need a cow.” This was the b  小题2: of Heifer International. Heifer International gives different k 小题3:  of gifts.  Its gifts might

say “quack” or “moo”.  Dan West asked friends in the United States to give gifts of heifers(小母牛), or young cows.  S小题4: then, Heifer International has given animals to four million families.  It gives people the chance to f  小题5:   themselves.

Heifers International wants the people they help to help others.  For one project, the group s 小题6:  chickens to some children in Asia.  The children yearned for(向往) the day when they could help others.  Nine-year-old Julie knew she had to look after her chickens w 小题7:  so they would produce new eggs and healthy chicks.  She t 小题8:  good care of them, and they gave birth to strong, healthy chicks.  Julie then passed on the gift of chicks to other families.

Because of Heifer International, children can s 小题9:  their days in a schoolhouse instead of working in the fields.  They can use the money they earn from their animals to pay for school.  Heifer International has made a huge d 小题10:  to people’s lives for many years.  People should be grateful to a kindhearted farmer named Dan West.
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