题干

如图为人体细胞的分裂、分化、衰老和死亡过程的示意图,图中①﹣⑥为各个时期的细胞,a﹣c表示细胞所进行的生理过程.据图分析,下列叙述正确的是(    )

A:⑤与⑥的基因型相同,蛋白质的种类也相同

B:人体细胞整体的衰老与死亡会引起衰老与死亡

C:图中有表示一个完整细胞周期的是abc阶段

D:与①相比,②的表面积与体积的比值增大,与外界环境进行物质交换的能力增强

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答案(点此获取答案解析)

B

同类题1

    Hi, everyone, I'm Jane. Two years ago, my husband bought me a bicycle. If you live in a town, it is often faster than a car and you don’t have to worry about parking. You can leave it anywhere. As it has a seat at the back and a basket in the front, I can take my small daughter to school, to the library, to the shops, and to anywhere.
    I use it most in summer when the weather is warm and dry. It can be very unpleasant in winter when it is cold and the snow is heavy. Of course, you must be careful on a bicycle. Accidents are not the only problem. One day I went shopping with my friends. But when I came back, I found that my bike's front wheel was missing. It was a long walk to the bicycle shop. Now I have three strong locks(锁).
    My husband uses my bicycle sometimes for short journeys. He says it is better than waiting for a bus. He still uses his car for longer journeys, but I think that all the sitting down is making him fat and lazy. I like riding on my bicycle because I can exercise a lot and get much fresh air, and this makes me feel much younger.
____ Jane thinks a bicycle is __________ than a car if you live in a town.
____ It's convenient to use a bicycle because you can ride it to anywhere and needn't worry about __________.
____ When it is __________ in summer, Jane rides her bicycle.
____ For short journey, Jane’s husband doesn’t want to wait for a bus. He would like to __________.
____ Jane can get a lot of __________ and fresh air, so she likes riding very much.

同类题4

阅读下文,回答问题。

                                                                                           越来越接近精神的天空

                                                                                                      李汉荣    

    人,在人群里行走寻找他的道路,在人群里说话寻找他的回声,在人群里投资寻找他的利润,在人群里微笑寻找回应的表情。生而为人,我们不可能拒绝人群,虽然,喧嚣膨胀的人群有时是那么令人窒息,让人沉闷,但我们终不能一转身彻底离开人群。

    人群是欲望的集结,是欲望的洪流。一个人置身于人群里,他内心里涌动的不可能不是欲望,他不可能不思考他在人群里的角色、位置、分量和份额。如果我们老老实实化验自己的灵魂,会发现置身人群的时候,灵魂的透明度较低,精神含量较低,而欲望的成分较高,征服的冲动较高。一颗神性的灵魂,超越的灵魂,丰富而高远的灵魂,不大容易在人群里挤压、发酵出来。在人群里能挤兑出聪明和狡猾,很难提炼出真正的智慧。我们会发现,在人口密度高的地方,多的是小聪明,绝少大智慧。在人群之外,我们还需要一种高度,一种空旷,一种庄静,去与天地对话,与万物对话,与永恒对话。伟大的灵魂、伟大的精神创造就是这样产生的。孔子独对大河而感叹时间的不可挽留:“逝者如斯夫,不舍昼夜”;庄子神游天外寻找精神的自由飞翔方式;佛静坐菩提树下证悟宇宙人生之般若智慧;法国大哲帕斯卡尔于寂静旷野发出哲人浩叹:“无限空间的永恒沉默使我恐惧”;李白“登高壮观天地间,大江茫茫去不还”,他不羁的诗魂飞越无限,把多半条银河引入人间,灌溉了多少代人的浪漫情怀;爱因斯坦把整个宇宙作为自己科学探究和哲学思考的对象,他认为人的最大成就和最高境界不过是通过对真理的求索,获得与宇宙对称的灵魂,由此,人变得辽阔而谦卑,对这个无限地存在着也永恒地包裹我们的伟大宇宙献上发自内心的敬意……正是这些似乎远离人群的人,为人群带来了太丰盛的精神礼物,在人群之上利益之外追寻被人群遗忘了的终极命题,带着人群的全部困惑和痛苦而走出人群,去与天空商量,与更高的存在商量,与横卧在远方也横卧在我们内心深处的“绝对”商量,然后将思想的星光带给人群,带进生存的夜晚。 

    为此我建议哲学家或诗人不该有什么“单位”,在“单位”里、在沙发上制作的思想,多半只有单位那么大的体积和分量,没有普世价值。把存在、把时间、把宇宙作为我们的单位吧,去热爱、去痛苦、去思想吧。 

    作为芸芸众生的一员,我也不愿总是泡在低处的池塘里,数着几张钱消费上帝给我的有限时光。我需要登高,需要望远,我需要面对整个天空作一次灵魂的深呼吸,我需要从精神的高处带回一些白云,擦拭我琐碎而陈旧的生活,擦拭缺少光泽的内心。 

    我正在攀登我的南山。目光和灵魂正渐渐变得清澈、宽广,绿色越来越多,白云越来越多,我正在靠近伟大的天空…… 

【注】这是作者《南山》系列散文中的一篇,南山位于作者故乡。