1.非选择题- (共1题)


(1)第一代杂交实验母本 雌果蝇,父本 雄果蝇。第二代杂交实验母本 雌果蝇,父本 雄果蝇。
(2)实验结果预测1
结论: 。
实验结果预测2 ,
结论: 。
II、果蝇的自然群体中,第II号染色体的变异很多。下表表示果蝇的三种第II号染色体突变类型(A、B、C)在不同温度下的存活能力与野生型果蝇的比较(以野生型为100)

分析表中数据,可看出生物突变的特点是 。如果果蝇生存环境的温度明显下降,经过较长时间后,类型 的基因频率会逐渐提高,进而形成一个新品种。如果这一新品种与原类型形成 ,就产生了一个新的物种。
2.选择题- (共1题)
Mary is an English girl, but she lives(居住) in China. She is six. Her mother says to her, “You are six now, Mary, you are going to school. I think it is very good. It's a nice school.”
“Is it a Chinese school?” Mary asks.
“Yes, it is.” Her mother says.
It is September and the new school year begins. Mary goes to school every day. She likes her lessons and her classmates(同学)very much. Her classmates like her, too. She always gets good grades(成绩) in math, so she often helps her friends with math. Mary thinks Chinese is too difficult, so she can't speak Chinese very well. But she likes the people of China and Chinese food very much.
根据短文内容,判断下列句子的正误。
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【1】题量占比
非选择题:(1道)
选择题:(1道)
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【2】:难度分析
1星难题:0
2星难题:0
3星难题:0
4星难题:1
5星难题:0
6星难题:0
7星难题:0
8星难题:0
9星难题:0