题干

病毒侵入人体后,血液中会出现相应的抗体。抗体的基本组成单位及合成抗体的细胞器分别是(   )

A:氨基酸和核糖体

B:氨基酸和高尔基体

C:核苷酸和核糖体

D:核苷酸和高尔基体

上一题 下一题 0.0难度 选择题 更新时间:2018-06-22 08:02:03

答案(点此获取答案解析)

A

同类题2

阅读下列短文,从每题所给的四个选项(A、 B 、C和D)中选出最佳选项。

The summer holidays are on their way! That means an end to your junior high school life. What do you have to say now it's all come to an end? Is there a special person you want to thank? Here's what some of our readers will be saying.

Li Chaoze, 16, Taiyuan, Shanxi:

I really want to say thank you to my grandmother. My parents work in another city. So I am living with my grandmother. She encouraged me and told me not to give up when I was sad and had no more hope for my life. I did what she told me to do. Now I am full of confidence again!

 

Wang Jia, 15, Nantong, Jiangsu:

    Lulu, my best friend, I have spent three years in junior high with you. I just heard that you will go abroad to study. I am sad I cannot study with you in the senior high school. But I know going abroad is your dream so I will also be happy for you. Wherever you go, just remember that we are best friends forever.

 

Zhang Jie, 14, Jinan, Shandong:

    I want to say sorry to my parents. My father and mother did a lot for me over my three years in middle school. Sometimes I saw my mother crying when I got low marks in my exams. Please trust me, Mom and Dad. I will keep trying until the end!

 

Zong Ze, 15, Xiamen, Fujian:

    I want to talk to Pan, the boy next door. Pan, you are my idol. You are so talented in English. I have worked hard for three years and I believe I will move up to your high school this year! We will be schoolmates. And I will join the School English Speech Competition next year.

    Thanks a lot for the above readers who share their feelings with us. And thanks a lot for the following two readers, Zhouling, 15, Shanghai and Jingmeng,14, Hangzhou. We can see their ideas in the next issue of our magazine.

同类题5

阅读下文,回答问题

源源本本

舒婷

    床垫晒过了,被单和窗帘等织物浆洗过了,冬菇和黄花菜因吸饱了阳光,黄灿灿地都密封贮存起来。一切都准备好,就等梅雨季节来临。

    可是,每天每天,太阳若无其事准时上班,阳光已慷慨得近似奢侈。道路依然干燥。人们开始频频眺望天空。在乡下,农民们忧郁地在田埂上走来走去,抽水机也搬出来了。报纸开始排出抗旱消息。

    望雨的心情犹如守候一位爱唠叨的老朋友。来得密了真觉得烦,在该来不来的时候,无论手上忙着什么,心总是慌慌地倾听着门外。

    于是忆起小时候背着书包在水洼边流连而屡屡迟到的事。尤其夏日骤雨初歇,无论马路上有多少灰尘和落叶,积水依然澄清,映出明净的天空,冉冉的云和摇动的树枝。童话里说有个孩子,失足掉进水洼,竟漫游了一个奇异的世界。至今我还信,只是这扇门需用幻想的眼睛来叩开。

    覆着绿苔的清泉,在怪石间迂回跳跃的小溪,卵石铺底的河流,都能使人喜悦。人在经过水的沐浴之后,重新变得柔韧、挺拔、新鲜。我曾经问我的老师蔡其矫:“何以有水源的地方都会唤起一种感动?”

    “因为,”他偏着头,仿佛听着心中的流水之声。“生命起源于水。”

    他接着问:“除了水,你最喜欢什么?”

    “植物。”我不假思索地口答。

    家中长辈们常说,我的手刚能离开母亲的衣角独立行走时,立即攥住了一支“草籽花”。我时常无限惊异于植物自己的语言和表情。经过训练的手可以创造闻名的插花艺术,但大自然花的部落却有自己的组合方式,而且更加和谐、优美,具有竞争的蓬勃生机。

    四岁的儿子对我说,“妈妈,葡萄还绿的时候摘它,它很痛,要是红了,它很高兴让我们采。”

    我惊讶地间:“你怎么知道的呀?”

    “因为我使劲拽,绿葡萄紧紧抓住枝条,熟了的时候,我们要忘了采,它就难过地一颗一颗落在地上。”

    我弯腰摸摸孩子的脸,像母树以枝条拂过它的腋芽。

    我和儿子有共同的经验。我的校园每年两次剪枝,我经过那些狼藉一地的权枝时,仿佛处在大屠杀之中。那四周无声的尖叫使我逃也似的飞跑,直跑到浑身发抖为止。

    是广州的植物园,使我好像接近了生命秘密的边缘。

    那是极普通的深秋初冬一个日子,云层很薄,阳光也不来装饰。水很静,完完全全。可能还很浅,但深绿色的浮游生物使水湾深邃幽远。水杉的华丽的树冠直垂到水面,看去像庞大的动物在饮水。庄严的水,安静的树,凤蹑足远去。我脚下的草地似乎渗出水来,凉凉的水意从我的脚跟导向全身。那一刻我迷迷惘惘地听到有无声的语言呼唤我,我全身都在主动回答。那树木始终严肃地凝视着,要提醒我一个雪亮的,然而却隔着层层云雾的秘密。

    也许,我曾经是它们的同类?

    我终究不能判断那些水杉和我交换的眼色该怎么翻译。但我发觉我盼雨的心情是一棵植物的爱恋和希望。

    可是,人类和水的关系不也是自然一个无可违抗的法则吗?