问题 填空题

某种自花传粉的豆科植物,不同品种植株所结种子的子叶有紫色和白色之分。现用该豆科植物甲、乙、丙三个品种的植株进行如下实验。分析回答:

(1)该植物种子子叶的紫色和白色这一相对性状中,显性性状是_________。如果用A代表显性基因,a代表隐性基因,则甲植株的基因型为________。

(2)实验三所结的紫色子叶种子中,能稳定遗传的种子占________。

(3)实验四所结的297粒紫色子叶种子中杂合子的理论值为_______粒。

(4)若将丙植株的花除去未成熟的全部雄蕊,然后套上纸袋,待雌蕊成熟时,接受乙植株的花粉,预期的实验结果为紫色子叶种子:白色子叶种子=_________。

答案

(1)紫色      AA、Aa

(2)0

(3)198

(4)1:1

阅读理解

任务型阅读。

     Julia Hill, an American woman, was born in 1974. She was 23 years old when she discovered that a

company wanted to cut down part of a forest in California. In the forest there were lots of redwood trees.

One of the trees was 70 metres tall and 1,000 years old.

     Julia wasn's happy about this. She traveled to California and climbed up the tree.  If I sit in the tree,"

she said, "the company can't cut it down." At the beginning, Julia planned to stay in the tree for two weeks.

She lived in a small treehouse and her friends were very helpful-they cooked food for her every day. She

used her mobile phone to talk to her family and to news reporters. She stayed in the tree day and night.

     Environmental organizations supported her, but other people weren't on her side and they tried to stop

her. The company used a helicopter that stayed near her treehouse for a long time. The helicopter was

very noisy and there was a lot of wind. Julia didn't like it, but she stayed in the tree.

     In the end, she was successful. The company agreed not to cut down the redwood. Finally, after two

years and eight days in the tree, Julia Hill climbed down and walked on the ground again. She and her

friends were very happy.

1. How tall and how old was the tree Julia Hill stayed in?

   The tree was _____ tall and _____ old.

2. 将画线句子翻译成汉语。

__________________________________________________.

3. 判断正误。

(     ) The company agreed not to cut down the redwood.

4. How long did Julia Hill stay in the tree? 

__________________________________________________.

5. Why did Julia Hill stay in the tree?

__________________________________________________.

多项选择题