题干

某种转基因玉米能高效合成一种多肽类的蛋白酶抑制剂,积累于茎叶中,让取食它的害虫的消化酶受抑制无法消化食物而死。下列就该玉米对人类安全性的评论中,不符合生物学原理的是     (   )

A:不安全。这种玉米的果实(种子)也可能含有蛋白酶抑制剂,食用后使人因无法消化食物而患病

B:不安全。该玉米的蛋白酶抑制剂基因可通过食物链富集并在人体细胞内表达,使人体无法消化食物而患病

C:安全。因为人与害虫消化酶的结构存在差异,玉米的蛋白酶抑制剂对人体很可能影响

D:安全。人类通常食用煮熟的玉米食品,玉米的蛋白酶抑制剂已被高温破坏,不会影响人的消化

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B

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      The freezing Northeast hasn't been a terribly fun place to spend time this winter, so when the chance came for a weekend to Sarasota. Florida. my bags were packed before you could say “sunshine. I left for the land of warmth and vitamin C(维生素C), thinking of beaches and orange trees. When we touched down to blue skies and warm air, I sent up a small prayer of gratefulness.Swimming pools, wine tasting, and pink sunsets(at normal evening hours, not 4 in the afternoon) filled the weekend, but the best part—particularly to my taste, dulled by months of cold­weather root vegetables—was a 7 a.m. adventure to the Sarasota farmers'market that proved to be more than worth the early wake­up call.

      The market, which was founded in 1979, sets up its tents every Saturday from 7 a.m. to 1 p.m., rain or shine, along North Lemon and State streets.Baskets of perfect red strawberries; the red­painted sides of the Java Dawg coffee truck; and most of all, the tomatoes:

amazing,large,soft and round red tomatoes.

      Disappointed by many a broken, vine­ripened(蔓上成熟的) promise, I've refused to buy winter tomatoes for years. No matter how attractive they look in the store, once I get them home they're unfailingly dry, hard, and tasteless.But I homed in, with uncertainty, on one particular table at the Brown's Grove Farm's stand,full of fresh and soft tomatoes the size of my fist.These were the real deal—and at that moment, I realized that the best part of Sarasota in winter was going to be eating things that back home in New York I wouldn't be experiencing again for months.

       Delighted as I was by the tomatoes in sight, my happiness deepened when I learned that Brown's Grove Farm is one of the suppliers for Jack Dusty, a newly opened restaurant at the Sarasota Ritz Carlton, where—luckily for me—I was planning to have dinner that very night.Without even seeing the menu, I knew I'd be ordering every tomato on it.