问题 选择题

流行性感冒的传染源是(  )

A.患者的生活空间

B.患流行性感冒的患者

C.患者使用过的毛巾

D.空气、飞沫

答案

传染病是指由病原体引起的,能在人与人之间、人与动物之间互相传染的一种疾病,引起传染病的细菌、病毒和寄生虫等生物称为病原体,传染病一般有传染源、传播途径和易感人群这三个基本环节,而传染源是指能够散播病原体的人或动物;传播途径是指病原体离开传播源到达健康人所经过的途径,如病人的排泄物,分泌物和传播疾病的生物或非生物媒介等;易感人群是指对某些传染病缺乏免疫力而容易感染该病的人群.

A、患者生活空间属于传播途径,不符合题意.

B、患流行性感冒的患者属于传染源,符合题意.

C、患者使用过的毛巾属于传播途径,不符合题意.

D、空气和飞沫属于传播途径,不符合题意.

故选:B

选择题
阅读理解

阅读理解

     As a kid, I can remember going to the supermarket and grabbing eggs off the shelf. I would run them

home to my mother because they were usually going into a delicious cake. Times  have  changed.  

Cagefree?  Organic?  Brown? White? Omega3s? Help! Here are some tips to help you figure out which

eggs you should choose:

     ●Brown or white? In fact,color is simply a sign of the breed of hen. Find the freshest egg with the

most flavor and let color be a secondary concern.

     ●Extra Omega3s? Omega3 eggs come from a hen whose diet has added flaxseed(亚麻籽) ,which

produces an egg containing an average of 225 mg of Omega3 fatty acids and Vitamin E. The countless

health benefits for humans make these eggs an attractive purchase. My opinion? Eat a piece of fresh fish

and get a pure dose of Omega3s. Let eggs be eggs.

     ●Does your egg need exercise? Freerange eggs are from hens raised without the confines of a cage,

though they may or may not have spent much time outdoors. Organic eggs are from hens whose feed

must meet organic standards. These hens must be raised humanely, and they must be given time to stay

outdoors. Hey,happier hens do lay tastier eggs.

     ●Does local make a difference? Nothing is better than local eggs. They may have a feather or two

stuck to them or be a little imperfect shape and they may or may not be certified (证明) organic;

however, they have one quality I prize:I know exactly where my food came from and how it came to

be! In some cases I can even ask the farmer when the eggs were laid and what the hens were fed.

1. What does the author think of Omega3 eggs?

A. They are a good choice for people to purchase.

B. They contain fewer Omega3s than fresh fish.

C. They have the highest content of pure Omega3s.

D. They are not the best source of Omega3s.

2. The underlined part “Freerange” probably means“________”.

A. wild      

B. organic

C. special    

D. Omega3free

3. According to the passage, which of the following has nothing to do with an egg's quality?

A. The egg's color.    

B. The hen's exercise.

C. The hen's living conditions.  

D. The hen's food.

4. This passage is most probably taken from a book named________.

A. Shopping Skills  

B. Eggs and Cooking

C. Raising Hens  

D. Healthy Diet