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读亚洲地形分布图,回答下列问题.

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同类题1

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     The World Meat Free Day for 2017 falls on 12, June, but what would actually happen if the whole world suddenly went vegetarian(素食的) permanently?

     If vegetarianism were accepted by everyone by 2050, the world would have about seven million fewer deaths every year. No meat would lower the chances of some diseases or even some cancers and so save the world 2-3% global GDP in medical bills. Food-related emissions would drop by around 60%. This would be due to getting rid of red meat which come from methane (甲烷) producing livestock (家畜) — from people's diets. Turning former pastures (牧场) into native habitats and forests would slow climate change and bring back lost biodiversity, including some animals which were previously pushed out or killed in order to keep cattle.

    However, farmers in the developing world could really suffer. Arid and semi-arid lands can only be used to raise animals as there's no or little water in these places, such as the Sahel land strip in Africa next to the Sahara; nomadic (游牧的) groups that keep livestock there would be forced to settle permanently and lose their cultural identities if there were no more meat. Losing meat also means that we also lose traditions. There's no more Christmas turkey. We would need to replace meat with nutritional substitutes, in particular for the world's estimated two billion-plus unhealthy or weak people for lack of nutrients. Animal products contain more nutrients per calorie than staples like grains and rice.

    Everybody currently engaged in the livestock industry would need to be retrained for a new career. This could be in agriculture, reforestation or producing bioenergy. Failing to provide career alternatives could lead to mass unemployment and social problems, particularly in traditionally rural communities.

同类题4

2004年12月,印度洋强震引起的海啸导致十多万人遇难,事后的遗体辨认只能借助于DNA杂交技术.该方法是从遗体和死者家属提供的死者生前的生活用品中分别提取DNA,在一定温度下,水浴共热,使DNA氢键断裂,双链打开.若两份DNA样本来自同一个体,在温度降低时,两份样本的DNA单链通过氢键连接在一起;若不是来自同一个体.则在两份样本中DNA单链在一定程度上不能互补.DNA杂交技术就能通过这一过程对面目全非的遗体进行辨认.请回答下列问题;

(1)人体DNA的主要载体是____,同一个人不同组织细胞的细胞核中DNA分子中(A+T)(G+C)是否相同?____,理由是____ 

(2)水浴供热能使DNA氢键断裂,皮肤生发层细胞中发生该变化的生理过程是____ 和____ .

(3)为了确保实验的准确性,需要克隆出较多的DNA样品.若一个只含31P的DNA分子杨平中腺嘌呤含量为15%,用32P标记的脱氧和概算为原料连续复制4次后不含32P的DNA分子占全部DNA的____ ,子代DNA分子中胞嘧啶的含量为____ 

(4)下表所示为分别从遗体和死者生前的生活用品中提取的三条相同染色体、同一区段DNA单链的碱基序列,根据碱基配对情况,A、B、C三组DNA中不是同一人的是____ ;

 

A组

B组

C组

遗体中的DNA碱基序列

ACTGACGGTT

GGCTTATCGA

GCAATCGTGC

家属的DNA碱基序列

TGACTGCCAA

CCGAATAGCT

CGGTAAGATG