问题 问答题 论述题

简要比较4种人体常见吸虫生活史的异同点。

答案

参考答案:

共同点:

1)成虫都寄生在人或其他哺乳动物体内。

2)完成生活史至少需要一个中间宿主。

3)第一(或唯一的)中间宿主为淡水螺。

4)虫卵都必须入水才能进一步发育。

5)都具有保虫宿主,均引起人兽共患寄生虫病。

6)在螺体内有无性增殖。

7)虫卵都可随粪便排出人体。

不同点:

1)成虫在体内的寄生部位不同,日本血吸虫寄生在门静脉肠系膜静脉。姜片虫寄生在小肠,华支睾吸虫寄生在肝胆管,卫氏并殖吸虫主要寄生在肺部。

2)中间宿主数目不同:日本血吸虫只需要一个中间宿主(钉螺),姜片虫有一个中间宿主(扁卷螺),华支睾吸虫有两个中间宿主(豆螺等和淡水鱼或虾),卫氏并殖吸虫有2个中间宿主(川卷螺和溪蟹或蝲蛄)。3)感染阶段和感染方式不同,日本血吸虫的感染阶段是尾蚴,经皮肤感染人。姜片虫、华支睾吸虫和卫氏并殖吸虫的感染阶段为囊蚴,经口感染人。

4)保虫宿主不同,日本血吸虫的保虫宿主主要是牛,姜片虫的保虫宿主主要是猪,华支睾吸虫和卫氏并殖吸虫的保虫宿主主要是猫、狗。

5)由于寄生部位不同及致病机制不同,所引起的症状和体征也不相同。

6)卫氏并殖吸虫的虫卵不仅可在粪便中找到,还可以经宿主的痰液排出,而其他3种吸虫的病原学诊断都为粪检虫卵。

单项选择题 A1型题
阅读理解

阅读理解。

     No one could have failed to be moved had he watched the live televised volleyball game between the

Chinese and Cuban women's teams. As we sat before the television set, with our eyes fixed on the screen, we experienced every kind of feeling. When the two teams played neck and neck, we were on pins and

needles, anxious as to what would come next, and when our team fell behind our hearts were in our

mouths. Watching the game between those two teams is not only a matter of great joy. For more than that

it provides food for thought. Just see how the Chinese women won the game by their cooperation (合作), by their excellent skill, their effort and strong will. A Chinese saying goes, "When two competent

opponents (比赛的双方) meet, the strong-minded one will win. "This is the spirit of the Chinese Women's Volleyball Team. If every Chinese showed some of the spirit, never losing heart in times of difficulty and

remaining clear-minded in times of advantage (优势), then our nation would stand in the vanguard (前列) of the world family of nations, just as the Chinese Women's Volleyball Team has done, is doing and will

do.

1. While watching the game, we _____.

A. had feelings of different kind

B. enjoyed a friendly and wonderful game

C. clapped and cheered only for the Chinese Women's Volleyball Team

D. were eager to know what would happen later on

2. The wonderful game _____.

A. brought us great joy

B. provided us with food for our thoughts

C. gave us not only great joy but also food for thoughts

D. give us a valuable amusement

3. The author believed that _____.

A. the Chinese Women's Volleyball Team was the strongest

B. China was sure to become stronger and stronger if only we have that spirit of the Chinese Women's

Volleyball Team

C. The Chinese must remain clear-minded in time of advantage

D. The Chinese Women's Volleyball Team never lost heart in times of difficulty

4. The best title of the passage might be _____.

A. Watching a Close Volleyball Game

B. The Spirit of the Chinese Women's Volleyball Team

C. Learn from the Members of the Volleyball Team

D. The Strong-Minded Are the Winners