问题 选择题

下列免疫类型不同于其他类型的是(  )

A.体液的杀菌作用

B.吞噬细胞的吞噬作用

C.皮肤的屏障作用

D.B淋巴细胞产生抗体,消灭病原体

答案

人体的第一道防线由皮肤和黏膜组成,它们不仅能够阻挡病原体侵入人体,而且它们的分泌物还具有杀菌作用,呼吸道黏膜上的纤毛还具有清扫异物的作用;人体的第二道防线由杀菌物质和吞噬细胞组成,能够杀灭和吞噬侵入人体的病原体;这两道防线是人人生来就有的,对多种病原体都有防御作用,属于非特异性免疫;人体的第三道防线由免疫器官和免疫细胞(主要是淋巴细胞)组成,当病原体进入人体后,会刺激淋巴细胞产生一种抵抗该病原体的特殊蛋白质,叫做抗体,抗体能够帮助人体清除或灭杀进入人体的病原体,抗体具有特异性,只对特定的病原体起作用,因此这种免疫属于特异性免疫.

体液的杀菌作用、皮肤的屏障作用、吞噬细胞的吞噬作用,都是人体生来就有的、对多种病原体具有防御作用,是非特异性免疫;B淋巴细胞产生抗体,消灭病原体是后天获得的、只对特定的病原体起作用,属于特异性免疫.

故选D

多项选择题
阅读理解

阅读理解

     In 1952, on the island of Koshima(越谷,日本某地), scientists were providing monkeys with sweet

potatoes dropped in the sand. The monkey liked the taste of the raw sweet potatoes, but they found the

dirt unpleasant. An 18-month-old female named Imo found she could solve the problem by washing the

potatoes in a nearby stream. She taught this trick to her mother. Her playmates also learned this new way

and they taught their mothers too. This cultural innovation was gradually picked up by various monkeys

before the eyes of the scientists.

     Between 1952 and 1958 all the young monkeys learned to wash the sandy sweet potatoes to make

them more palatable(美味的). Only the adults who imitated their children learned this social improvement.

Other adults kept eating the dirty sweet potatoes.

     Let us suppose that when the sun rose one morning there were 99 monkeys on Koshima Island who

had learned to wash their sweet potatoes. Let's further suppose that later that morning, the hundredth

monkey learned to wash potatoes. Then it happened. By that evening almost everyone in the tribe was

washing sweet potatoes before eating them. The added energy of this hundredth monkey somehow

created an ideological breakthrough!

     But notice: A most surprising thing observed by these scientists was that the habit of washing sweet

potatoes then jumped over the sea colonies of monkeys on other islands and the mainland troop of

monkeys at Takasakiyama(高岐山)began washing their sweet potatoes. Thus, when a certain critical(关键的)number achieves an awareness, this new awareness may be communicated from mind to mind.

Although the exact number may vary, this Hundredth Monkey Phenomenon(现象)means that when only a limited number of people know of a new way, it may remain the conscious property(个人意识性属性)of those people.

     But there is a point at which if only one more person comes to a new awareness, a field(能量场)is

strengthened so that this awareness is picked up by almost everyone!

     Your awareness is needed. You may be the "hundredth monkey"

1. The passage may be adapted from __________.

A. a text book

B. a newspaper

C. an advertisement

D. a scientific report

2. It was __________ that found the way to make potatoes clean by washing them.

A. a young clever female monkey

B. an old experienced monkey

C. an 18-year-old mother monkey

D. a monkey finding a potato in the river

3. The last sentence of Paragraph 1 "This cultural innovation was gradually picked up by various monkeys before the eyes of the scientists." implies that __________.

A. monkeys have learnt the new way unconsciously(下意识地)

B. monkeys like picking up things on the ground

C. it is very difficult for monkey to learn a new way

D. monkeys learnt the new way from scientists

4. According to the writer, the hundredth monkey __________.

A. is the last one to learn to wash potatoes

B. is the most stupid in learning

C. makes a great difference in spreading a new way

D. plays a small part in the breakthrough

5. The write wrote the last paragraph __________.

A. to draw a conclusion that one day monkeys will become human beings

B. to predict that one day every reader can turn into the hundredth monkey  

C. to encourage people to learn more knowledge

D. to emphasize the importance of each person's contribution to spreading a new method