Jim, Tom and Tim are in the park. It's a small park, but it's nice. They can see some animals there. There are some birds in the tree. They are yellow. They can fly high. Quack… Quack… What do you hear? Oh，Some ducks. They can swim in the water. There are seven white ducks and nine black ducks. What's that? It's a cat. It's under the tree. It's white. It can jump very fast. The children like the small animals very much.

青少年学生要承担起对社会、对国家的责任，需要我们了解我国的基本国情。目前我国的基本国情是（  ）

补写出下列句子中的空缺部分。

①《论语》记载的孔子言论中，用“云”作比喻，形象地表述对“富贵”态度的句子是“____， ____。”

②儒道两家都曾用行路来形象论述积累的重要性。《老子》“九层之台，起于垒土；千里之行，始于足下。”荀子《劝学》“____，____；不积小流，无以成江海。”

③《念奴娇·赤壁怀古》描述周瑜轻松地指挥战争取得胜利的两句是“____，____。”

下列有关性别遗传的说法中，错误的是（  ）

由于编码酶X的基因中某个碱基被替换，酶X变为酶Y。下表显示，酶Y与酶X相比，可能出现的四种状况。下列有关分析，合理的是（   ）