1. GWD:一个是老鼠眼病那道。GWD-13-40
In response to viral infection, the immune systems of mice typically produce antibodies that destroy the virus by binding to proteins on its surface. Mice infected with a herpesvirus generally develop keratitis, a degenerative disease affecting part of the eye. Since proteins on the surface of cells in this part of the eye closely resemble those on the herpesvirus surface, scientists hypothesize that these cases of keratitis are caused by antibodies to herpesvirus.
Which of the following, if true, gives the greatest additional support to the scientists’ hypothesis?
- Other types of virus have surface proteins that closely resemble proteins found in various organs of mice.
- There are mice that are unable to form antibodies in response to herpes infections, and these mice contract herpes at roughly the same rate as other mice.
- Mice that are infected with a herpesvirus but do not develop keratitis produce as many antibodies as infected mice that do develop keratitis.
- There are mice that are unable to form antibodies in response to herpes infections, and these mice survive these infections without ever developing keratitis.
- Mice that have never been infected with a herpesvirus can sometimes develop keratitis.
2. GWD:一个是牛肉过剩,价格下降,牛肉饲料价格上涨,但是短期内肉价还会下降,问原因 GWD-7-Q37
Escalating worldwide demand for corn has led to a sharp increase in the market price of corn, and corn prices are likely to remain high. Corn is extensive used as feed for livestock, and because profit margins are tight in the livestock business, many farmers are expected to leave the business. With fewer suppliers, meat prices will surely rise. Nonetheless, observers expect an immediate short-term decrease in meat prices.
Which of the following, if true, most helps to justify the observers’ expectation?
- The increase in corn prices is due more to a decline in the supply of corn than to a growth in demand for it.
- Generally, farmers who are squeezed out of the livestock business send their livestock to market much earlier than they otherwise would.
- Some people who ate meat regularly in the past are converting to diets that include little or no meat.
- As meat prices rise, the number of livestock producers is likely to rise again.
- Livestock producers who stay in the business will start using feed other than corn more extensively than they did in the past.
3. 转基因玉米,一般是变大,也有变小的,问为什么要变小?答案是防风
4. 要建电厂在一个地方,煤量大,所以成本便宜,但是本地电力富裕,要往外输,往外输要钱。还是预计能赚钱。问加强
5. 政府推行戒烟,来减少医疗开支,专家说戒烟后人会发胖,发胖更容易引发疾病,所以没用。问削弱。
6. 说一个水域有某种鱼要从下游到上游去产卵,然后由于什么原因造了一个大坝,原来每年有几千条鱼在产卵期游到上游,结果修坝以后只有几百条去上游了,结论说大坝有缺陷,问weaken。 记得答案有一个说那些到上游产卵的鱼产完就没游回去;另一个说因为造坝的关系,某些有毒物质污染了下游的河水(我选的是这个,原因是大坝并没有缺陷,而是因为造坝导致的关系,不知道对不对) |