2008年1月12日我国科考队员登上了南极“冰盖之颠”．他们生理上出现的适应性变化是（　　）

①体温下降   ②机体耗氧量降低  ③皮肤血管收缩   ④体温调节中枢兴奋性增强     ⑤甲状腺激素分泌量增加．

阅读下面短文，从短文后各题所给的四个选项(A、B、C和D)中，选出一个最佳选项。   
    “Daddy, can I have a piece of cake？” my oldest son asked me.
We had just been to the gym and stopped to eat at the restaurant.
    “No，” I replied, “you don't need a piece of cake.”
My son 1 15 in a few days. He 2  over 6 feet tall. He is very slim and athletic in shape . It was not always that way. My wife wrote a book about the challenge and   3   of getting him fit. He now takes it  4  and looks as if he's never been overweight in his life.
    He had a full plate of vegetables and tofu.  He didn't need a piece of cake.  5 ， everything in the restaurant is quite  6 . Our dinners could have  7 a family of seven at a fast food restaurant. That cake probably  8 $5.
    He was silent as he looked at the delicious cakes. I had forgotten that I had walked over to the cake shelf while he was   9 his food from the buffet (自助餐)．
    I looked at my plate. There sitting on the edge was a piece of 10. I looked at it wondering but also knowing how it got there. “We will divide it，” I said.
    A few days later my oldest son was  11me again. We stopped at a   12  . He ordered a sandwich. I then13 two sandwiches. He immediately barked, “Can I have two？” He wanted 14what Daddy had.
    Your kids are very   15 to put on their trays, exactly what you have on yours, and I think this applies to (适用于) more than food. Keep your life plate with only what you want your kids to have.

甲、乙同学分别做“测定小灯泡的电功率”实验，他们使用的器材中，电源电压相同且不变（为1.5伏的整数倍），滑动变阻器两个（分别标有“10Ω  2A”和“20Ω  2A”字样），待测的两小灯额定电压分别为2.2伏和6.3伏．甲、乙两同学各自选取一个变阻器、小灯及其它器材按要求正确连接电路，并进行实验．甲同学闭合电键后，发现移动滑动变阻器的滑片时电压表、电流表示数均有变化，但是小灯发光始终较暗；乙同学闭合电建后，观察到电流表示数为0.14安，当滑片移动到中点时（即滑动变阻器接入一半的电阻），小灯正常发光．

实验中所用的电源电压为____伏．乙同学所测小灯的额定电功率为____瓦，选用的滑动变阻器最大阻值为____欧．

已知一段演绎推理：“一切奇数都能被3整除，（2⁵+1）是奇数，所以（2⁵+1）能被3整除”，则这段推理的 （　　）

图为动物生殖发育过程图解．请根据图回答有关问题：

（1）A过程表示细胞的____ 分裂，D和E过程中细胞进行____ 分裂，A，B，C过程的意义是____ ．

（2）人类的性别决定发生在____ 过程（填字母），男性的体细胞中染色体组成是____ ．