苗期发病幼苗呈猝倒状，病苗四周生白色棉状物，成株叶片发病，呈

搜题请搜索小程序“爱下问搜题”

问题单项选择题

苗期发病幼苗呈猝倒状，病苗四周生白色棉状物，成株叶片发病，呈水浸状暗绿色至暗褐色病斑，这是辣椒（）的症状。

A.灰霉病

B.疫病

C.炭疽病

D.枯萎病

答案

参考答案：B

补全对话，情景问答

根据所给情景完成对话，每空一词。

Kate: Excuse me.

Tom: Yes?

Kate: Could you tell me 1 the hospital is?

Tom: I can't understand you. Would you say it 2_____, please?

Kate: I'd like to 3___ which is the 4__ to the hospital.

Tom: Well, let me see. Go 5_____ this street then 6 left at the second

crossing. Go on till you reach the end of the 7 _ , then you'll see it.

Kate: Is it far from here?

Tom: Yes, it is. You can 8 a bus. The bus 9 _ is just over there.

Kate: Thank you very much.

Tom: That's all 10 _ _.

单项选择题案例分析题

反转录病毒科的病毒因带有以RNA为模板合成DNA的反转录酶而得名。已经发现人免疫缺陷病毒有HIV-1和HIV-2，两型病毒的核苷酸序列相差超过40%。HIV-1是引起全球艾滋病流行的病原体，HIV-2主要局限于西部非洲，且毒力较弱，引起的艾滋病特点是症状轻、病程长。

AIDS的病原体主要是（）

A.HTLV-1型

B.HTLV-2型

C.HTLV-5型

D.HIV-1型

E.HIV-2型