题干

吞噬细胞对细菌抗原的吞噬、加工处理和呈递过程如图所示.下列叙述错误的是(    )

A:吞噬细胞能吞噬细菌抗原

B:溶酶体参与抗原的加工处理过程

C:加工处理后的抗原直接呈递给B细胞

D:抗原加工处理和呈递过程既存在于体液免疫,也存在于细胞免疫

上一题 下一题 0.0难度 选择题 更新时间:2015-03-25 08:28:42

答案(点此获取答案解析)

C

同类题4

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    On Friday, Germany's telecom regulator(电信业管理者), the Federal Network Agency, announced that a number of children s smartwatches, designed for ages 5 to 12, can allow someone to remotely tap into the watch s microphone and secretly spy from remote places. The regulator isn't just worried about the potential of people spying on children-it's worried the devices(设备) can be used to spy on anyone.

    And in Germany, it's illegal to record private conversations without permission. "According to our investigations, parents were using the watches, for example, to listen in on their children during class, said Federal Network Agency President Jochen Homann in a statement.

    Smartwatches that make phone calls, like the Apple Watch, are legal in Germany. The problem with many of the children's smartwatches, however, is that the devices have a classic spying function, similar to a baby monitor, which can be easily activated (激活) just by using an app.

    The German regulator is so serious about destroying these devices. It's asking citizens to document the watches' destruction and file evidence online. Once the watches are destroyed, the regulator will provide a "certificate of destruction," confirming the deed was done.

    This isn't the first time the Federal Network Agency told German citizens to destroy a consumer device. The regulator once prohibited the doll "My Friend Cayla", which was fitted with radio transforming technology that could allow children to be spied on.

    Remind tech producers: The German government won't just ban devices that can spy on anyone, they'll demand the devices be destroyed with hammers (or whatever means of destruction one prefers) — even if they're dolls.

同类题5

阅读下文,回答问题

苦难中走来的阳光少年

    他是2017年清华大学录取名单里一个普通的名字,然而他的名字却响爆众多媒体,成为2017年“超级网红”。他18岁的苦难人生和阳光励志故事正激励和感动着无数人。他就是河北省吴桥县理科状元—庞众望!

    那一年,他上初二,常年瘫痪在床的母亲严重贫血住院,而父亲患有精神分裂症,照顾母亲的重担就落在他弱小的肩膀上。为了生活下去,他不但要照顾母亲,还要到饭店打零工赚生活费。

    有一天放学后,他跑到菜市场,捡拾烂菜叶,背后传来了同情和鄙夷参杂的声音:“这个捡垃圾的孩子,真可怜!”“孩子,你不好好学习,将来就会像他一样捡垃圾!”

    “捡垃圾”三个字严重挫伤了众望年少的心灵,没错,他从七岁懂事起,便踏上了捡垃圾的生活,整整6年,他在捡垃圾的生活中上完了小学。

    他低着头迅速逃离菜市场,逃离人群,悲伤的泪水顺着脸颊流淌。回去的路要过一个山坡,刚刚经历一场暴雨,泥石流冲刷了草木,很多小树被摧残,众望看着这弱小的生命被摧残的样子,忽然联想到自己,尚未擦干的泪水再一次汹涌而出。这就是命运吧,自己苦难的生命,像极了眼前的这棵小树。

    他边走边想着自己的种种苦难,泪水禁不住一次次汹涌而出。哭累了,也走不动了,他跌坐在山路旁淤泥石块堆积的石堆上,抬头时,看到这个乱石堆中一棵小树挺拔地站立着,比旁边一片片小树都高出一头。为什么这棵小树能高出一截?他恍然大悟,泥石流涌来的碎石泥土堆在这棵小树的根部,使得这棵树比别的树生存更艰难却更激发了它顽强的生命力。

    他突然感到丛未有过的力量,内心忽然变得强大起来。他快速赶回医院旁的饭店,干完零活,借着店里的锅炒了捡来的菜叶。夜深了,当他把热腾腾的饭菜端回医院病房,母亲心疼地抱住儿子痛哭流涕。众望安慰说:“妈妈,快吃吧,不要心疼我, 我已经是男子汉了,我可以保护照顾您一辈子!”那一晚,众望在日记里写下了这段话:“……”

    从此,他始终保持着阳光般的笑容,艰难的处境,更加激发了他坚强的内心和感恩的情怀。整个初中和高中,一边是生活的压力,一边是繁重的学习任务,众望边照顾贫寒的家,一边发愤学习,一张张奖状,一份份优异的成绩单,成为这个家庭生命的支柱!

    2017年高考,庞众望脱颖而出,成为河北省吴桥县理科状元。得知被清华大学录取的那一刻,阳光少年忍不住流下了激动的泪水,他庆幸自己没有被苦难的人生击垮。

    是的,每一个卑微的生命都有一颗坚强的心,就像弱小的树苗在风雨中坚强生长。当苦难和厄运不可避免地降临,不要沉沦和绝望,敞开胸怀去接纳苦厄,感恩生命,用乐观向上的信念和真挚之爱的力量去努力生活,苦难也会开出阳光般的花朵。

(选自《思维与智慧》)