试题与答案

下图是南瓜的发育过程示意图,请据图回答: (1)雄蕊的____里的花粉散出后,

题型:实验题

题目:

下图是南瓜的发育过程示意图,请据图回答:

(1)雄蕊的____里的花粉散出后,以一定方式传送到雌蕊的柱头上,叫做传粉。传粉是受精的前提。

(2)图中的[4]是由[2]中的           发育来的。

(3)在图中[5]所示的生理过程中,消耗的营养物质主要来 自               。 

(4)请你当一次农业技术员,菜农利用某种技术,在南瓜植株上收获黄瓜,这种技术叫做           

答案:

(1)花药(2)胚珠 (3)子叶 (4)嫁接

分析:此题考查了花的结构传粉和受精,以及种子和果实的形成、种子萌发、嫁接等知识点.据此解答.

解答:解:(1)从雄花的花药中散落到雌花的雌蕊柱头上表示的生理过程是(异花)传粉.

(2)我们可以看出图中的[4]是种子由[2]中的胚珠发育而来;

(3)南瓜的种子属于双子叶植物,其营养物质储存在子叶中,图中[5]表示南瓜种子的萌发,所以在种子萌发时消耗的营养物质主要来自子叶.

(4)嫁接是指把一个植物体的芽或枝,接在另一个植物体上,使结合在一起的两部分长成一个完整的植物体.被接上去的芽或枝叫接穗,被接的植物叫砧木,嫁接时应当使接穗和砧木的形成层紧密结合,以确保成活.因此菜农利用某种技术,在南瓜植株上收获黄瓜,这种技术叫做嫁接.

故答案为:(1)传粉;(2)胚珠; (3)子叶; (4)嫁接.

点评:本题考查到植物的一生,同学们可借助植物的一生为轴线将有关开花、传粉、结果、萌发、芽、茎等知识联系在一起.

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题型:阅读理解

阅读理解。

     You've attended all the classes,done all of your homework and you think you have grasped

the material.But then the day of the test comes.Suddenly,you feel so nervous that you can't answer

those questions you knew the answers to just last night.If this sounds like you,you may have a

case of test anxiety (焦虑).

     Test anxiety can be a real problem.When someone is stressed out over a test,he or she

may not be able to do his or her best work.Feeling ready to meet the challenge,though,can keep

test anxiety at a proper level.

     Use a little stress to your advantage.Stress is your body's warning mechanism (装置)-it's

a signal that helps you prepare for something important that's about to happen.Instead of worrying

too much about the test,take  an active way.Let stress remind you to study well before a test.Then

you'll stop your stress from being out of control.

     Ask for help.Although a little test anxiety can be a good  thing,too much of it is another story

entirely.If sitting for  a test makes your mind go blank and causes you to miss answers that you know,

then your level of test anxiety  probably needs some attention.Your teacher,your parents,or a tutor

can be a useful resource to talk to if you always get too much test anxiety.

     Be prepared.Many students find that their  test anxiety is  reduced when they start to study better.

It works-the better you know the material,the more confidence you'll have.

1.What is this passage mainly about?

A.What should be done before a test.

B.How to deal with test anxiety.

C.What causes test anxiety.

D.What test anxiety is.

2.The underlined word "grasped" in Paragraph 1 probably means________.

A.received    

B.passed

C.understood  

D.finished

3.From Paragraphs 2 and 3 we can learn that________.

A.it's hard to keep test anxiety at a proper level

B.test anxiety cannot be avoided

C.only lazy students have test anxiety

D.a little test anxiety might be helpful

4.In Paragraph 4,the writer suggests a student who feels too nervous before a test should________.

A.find a quiet place to relax for a while

B.talk to someone to get over the anxiety

C.have a good time with some friends  

D.find out if others feel the same

5.What can we infer from the passage?

A.Test anxiety is a kind of serious illness.

B.Getting prepared can reduce test anxiety.

C.Only teachers can help students get over test anxiety.

D.The more tests a student has,the less anxiety he/she will have.

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