问题 解答题

如图为某同学在显微镜下观察并绘制的甲、乙两个细胞图,请据图回答:

(1)甲图2中具有控制生物性状的______.

(2)乙图中的7是______,5是______,能够阻止喷洒在果实表面的农药进入果实的细胞中.

答案

(1)甲图是一个动物细胞的结构图,1是细胞膜,3是细胞质,2是细胞核,细胞核中有染色体,染色体中有DNA和蛋白质,DNA上有遗传信息--基因,基因控制生物的性状.

(2)、乙图中的4是细胞壁,有保护和支持作用,5是细胞膜,能控制物质的进出,6是细胞质,具有流动性,加速细胞内外物质的交换,7是染色体,内有DNA和蛋白质,DNA上有遗传信息--基因,基因控制生物的性状.

故答案为:(1)基因  

(2)染色体;细胞膜

单项选择题
阅读理解

阅读理解。

     Every day we experience one of the wonders of the world around us without even realizing it. It is not

the amazing complexity of television, nor the impressive technology of transport. The universal wonder we

share and experience is our ability to make noise without mouths, and so transmit ideas and thoughts to each

other's minds. This ability comes so naturally that we tend to forget what a miracle (奇迹) it is.

     Obviously, the ability to talk is something that marks humans off from animal. Of course, some animals

have powers just as amazing, Birds can fly thousands miles by observing positions of the stars in the sky in

relation to the time of day and year. In Nature's talent show, humans are a species of animal that have

developed their own special act. If we reduce it to basic terms, it's an ability for communicating information

to others, by varying sounds we make as we breathe out.

     Not that we don't have other powers of communication. Our facial expressions convey our emotions, such

as anger, or joy, or disappointment. The way we hold our heads can indicate to others whether we are happy

or sad. This is so-called "body language". Bristling (直立的) fur is an unmistakable warning of attack among

many animals. Similarly, the bowed head or drooping tail shows a readiness to take second place in any animal

gathering.

     Such a means of communication is a basic mechanism that animals, including human beings, instinctively

acquire and display. Is the ability to speak just another sort of instinct? If so, how did human beings acquire

this amazing skills? Biologist can readily indicate that particular area of our brain where speech mechanisms

function, but this doesn't tell us how that part of our bodies originated in our biological history.

1. According to the passage, the wonder we take for granted is _____.

A. our ability to use language

B. the miracle of technology

C. the amazing power of nature

D. our ability to make noises with mouth

2. What feature of "body language" mentioned in the passage is common to both human an animals?

A. Lifting heads when sad.

B. Keeping long faces when angry.

C. Bristling hair when ready to attack.

D. Bowing heads when willing to obey.

3. What can be inferred from Paragraph 3?

A. Body language is unique to humans.

B. Animals express emotions just as humans do.

C. Humans have other powers of communication.

D. Humans are no different from animals to some degree.

4. This passage is mainly about _____.

A. the development of body language

B. the special role humans play in nature

C. the power to convey information to others

D. the difference between humans and animals in language use