题干

甲、乙、丙是三种微生物,下表I、Ⅱ、Ⅲ是用来培养微生物的三种培养基。甲、乙、丙都能在Ⅲ中正常生长繁殖;甲能在I中正常生长繁殖,而乙和丙都不能;乙能在Ⅱ中正常生长繁殖,甲、丙都不能。下列说法正确的是(  )
 
粉状硫
10g
K2HPO4
4g
FeS04
0.5g
 蔗糖
10g
(NH4)2SO4
0.4g
  H20
100ml
 MgS04
9.25g
 CaCl2
0.5g
I
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A:甲、乙、丙都是异养微生物

B:甲、乙都足自养微生物、丙是异养微生物

C:甲是异养微生物、乙是固氮微生物、丙足自养微生物

D:甲是固氮微生物、乙是自养微生物、丙是异养微生物

上一题 下一题 0.0难度 选择题 更新时间:2019-01-12 05:09:44

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D

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    Only two countries in the advanced world provide no guarantee for paid leave from work to care for a newborn child. Last spring one of the two, Australia, gave up the bad distinction by setting up paid family leave starting in 2011. I wasn't surprised when this didn't make the news here in the United States — we're now the only wealthy country without such a policy.

    The United States does have one explicit family policy, the Family and Medical Leave Act, passed in 1993. It entitles workers to as much as 12 weeks' unpaid leave for care of a newborn or dealing with a family medical problem. Despite the modesty of the benefit, the Chamber of Commerce and other business groups fought it bitterly, describing it as “government-run personnel management” and a “dangerous precedent (先例).” In fact, every step of the way, as (usually) Democratic leaders have tried to introduce work-family balance measures into the law, business groups have been strongly opposed.

    As Yale law professor Anne Alstott argues, justifying parental support depends on defining(定义) the family as a social good that, in some sense, society must pay for. Parents are burdened in many ways in their lives: there is “no exit” when it comes to children. Society expects — and needs — parents to provide their children with continuity of care. And society expects — and needs — parents to persist in their roles for 18 years, or longer if needed.

    While most parents do this out of love, there are public punishments for not providing care. What parents do, in other words, is of deep concern to the state, for the obvious reason that caring for children is not only morally urgent but important to the future of society. To classify parenting as a personal choice for which there is no collective responsibility is not merely to ignore the social benefits of good parenting; really, it is to steal those benefits because they accrue (累积) to the whole of society as today's children become tomorrow's citizens. In fact, by some estimates, the value of parental investments in children, investments of time and money, is equal to 20-30% of GDP. If these investments bring huge social benefits — as they clearly do — the benefits of providing more social support for the family should be that much clearer.