题干

下列人体细胞中分化程度最低的是

A:胚胎干细胞

B:造血干细胞

C:红细胞

D:肌细胞

上一题 下一题 0.0难度 选择题 更新时间:2017-12-13 12:31:52

答案(点此获取答案解析)

A

同类题1

阅读下面短文,掌握其大意,然后从各小题所给的四个选项中选出最佳选项。

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Best Learners

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同类题4

阅读下面甲、乙两段选文,回答下列各题。

【甲】

       嗟夫!予尝求古仁人之心,或异二者之为,何哉?不以物喜,不以己悲。居庙堂之高则忧其民;处江湖之远则忧其君。是进亦忧,退亦忧。然则何时而乐耶?其必曰“先天下之忧而忧,后天下之乐而乐”乎。噫!微斯人,吾谁与归?

(选自《岳阳楼记》)

【乙】

       杨万里为人刚而偏.孝宗始爱其才,以问周必大,必大无善语,由此不见用。韩侂胄用事,欲网罗四方知名士相羽翼,尝筑南园。属万里为之记,许以掖垣。万里曰:“官可弃,记不作可。”侂胄恚,改命他人。卧家十五年,皆其柄国之日也。侂胄专僭日益甚,万里忧愤,怏怏成疾。家人知其忧国也,凡邸吏之报时政者皆不以告。忽族子自外至,遽言侂胄用兵事。万里恸哭失声,亟呼纸书曰:“韩侂胄奸臣,专权无上,动兵残民,谋危社稷,吾头颅如许,报国无路,惟有孤愤!”又书十四言别妻子,落笔而逝。

(选自《宋史•杨万里传》)

      【注】①杨万里:南宋著名诗人,力主抗金。②偏:固执。③孝宗:指宋孝宗赵昚(shèn).④韩侂(tuō)胄:南宋重臣,以外戚身份专政十多年,位在左右丞相之上。⑤掖垣:泛指高官。⑥僭(jiàn):超越本分。⑦邸(dǐ):此指官府。⑧族子:宗族里的年轻人。⑨吾头颅如许:意为我头发已白,年已老。