题干

某学校生物活动小组发现一种野生植物,这种植物有的开红花,有的开白花,茎秆有绿色的也有紫色的。此小组针对该植物的花色(设由R、r基因控制)和茎色(设由Y、y基因控制)进行了两组杂交实验,结果如下表所示。请分析回答:

实验组别

杂交组合

子代的表现型和植株数目

红花紫茎

红花绿茎

白花紫茎

白花绿茎

白花紫茎×红花紫茎

416

138

410

137

白花紫茎×白花绿茎

142

134

421

418

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同类题5

假如你叫张明,你的外国朋友John发来邮件,请你介绍中国的传统节日.请根据表格内容提示及要求给他写一封80﹣100词的回信.

 Festivals

 time

 food

 activities

 meanings

1

the Lantern Festival

is January or February

yuanxiao

watch lantern shows and dragon dances

pray for health and happiness for the whole year

2

the Mid﹣Autumn Festival

in the middle of autunm

mooncakes

watch the moon:tell the story of Chng'e

celebrate harvest;gei together with the family

3

参考词汇:pray for祈求;harvest丰收

要求:

    1).描述节日1和节日2,并自主选择节日3进行介绍,包括节日名称、时间、美食、活动方式及意义等;

    2).语言通顺,要点齐全,意思连贯,条理清楚,书写规范;

    3).文中不得出现真实的姓名和学校名称;

    4).文章开头和结尾已给出,不计人总词数.

Dear John,

    Glad to receive your email.You asked me about festivals in China.Let me introduce some important ones to you.

    First of all,I want to introduce the Lantern Festival.It comes in January or February.   …………

…………………………………………………………………………………………………………………………………………………………

…………………………………………………………………………………………………………………………………………………        

    Can you tell me something about the festivals in your country?I'm looking forward to hearing from you.

                                                                           Yours.

Zhang Ming