题干

下列实例可以说明细胞具有全能性的是(  )

A:皮肤被划破后,伤口重新愈合

B:蜥蜴受攻击断尾后重新长出尾部

C:造血干细胞增殖分化产生各种血细胞

D:胡萝卜组织块经离体培养产生完整植株

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D

同类题2

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福建土楼

    ①福建土楼是东方文明的一颗明珠,它被誉为“东方古城堡”、“世界建筑奇葩”,“世界上独一无二的、神话般的山区建筑模式”。

    ②风格奇异的土楼民宅散布在闽西的永定、武平、上杭及闽西南的南靖、平和、华安、漳浦等地。其造型、装饰和建造工艺世所罕见,土楼,俗称“生土楼”。因其大多数为福建客家人所建,故又称“客家土楼”。它是以生土作为主要建筑材料,掺上细沙、石灰、糯米饭、红糖、竹片、木条等,经过反复揉、舂、压建造而成。楼顶覆以火烧瓦盖,经久不损。土楼高可达四五层,供三代或四代人同楼聚居。

    ③福建土楼大多具备完善的防御功能。其外墙厚一至二米,一二层不开窗,仅有坚固大门一关,土楼便成坚不可摧的堡垒。为防火攻,门上设有漏水漏沙装置,紧急时楼内居民还可从地下暗道逃出。如今,土楼早已不再是堡垒,但那些完备而精致的防御设施,仍让人们拍案惊奇。

    ④厚重的福建土楼,承载着厚重的传统文化。发人深省的楹联匾额,与楼共存的私塾学堂,教化育人的壁画彩绘,无不激荡着历朝历代土楼人家“修身齐家”的理想和“止于至善”的追求。振成楼有副楹联备受称道:振作哪有闲时,少时壮时老年时,时时须努力;成名原非易事,家事国事天下事,事事要关心。

    ⑤2008年7月福建土楼被列为世界文化遗产。

同类题3

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    Everyone, from homeless people to billionaires, is likely to be influenced by stress; there's simply no way to avoid it ____ Here are five powerful tips for ways to kill stress in almost any situation.

Eat Healthier

    Though a lot of stress is psychological, there are also plenty of physical factors that lead to this natural human response to noticed danger, In order to relieve stress, make sure you're treating your body right. A big part of this is eating healthier ____ Anyway, adopting an alkaline(碱性的)diet instead of an acidic (酸性的)one is recommended.

Wake Up Earlier

    ____ However, waking up 15 or 20 minutes earlier each morning may have more benefits than sleeping in. By giving yourself some extra time, you won't feel quite rushed in the morning, which leads to better preparation and more confidence.

____

    Since you are never going to remove 100 percent of the stress in your life, one of the best things you can do is let it be one of your motivations. This is what stress is designed to do, after all. The psychological and physical reactions brought on by stress are supposed to heighten our senses and empower us to fight off a threat.

Watch a Funny Video

    Here is a simple and practical tip: watch a funny video on You Tube, Research shows that seeing something amusing activates the part of the brain that produces calm physiological(生理的)responses. This can lead to less anxiety and more happiness.

Take Walk Outside

    Whenever possible, make sure you take your walk outdoors ____ It can improve energy levels and memory by as much as 20 percent.

A.A number of studies are two important keys to good health.

B.Diet and relaxation are two important keys to good health.

C.There are no magic”anti-stress”foods.

D.However, there are ways to reduce the amount of stress you suffer from.

E.Keep Positive Relationships

F.Let Stress Motivate You

G.It is certainly true that the more sleep you get, the less stressed you'll be.