如图,已知直线l1∥l2∥l3∥l4,相邻两条平行直线间的距离都是1,如果正方形ABCD的四个顶点分别在四条直线上,则sinα=(  ) 您所在的位置:网站首页 距离度量需满足的基本性质有 如图,已知直线l1∥l2∥l3∥l4,相邻两条平行直线间的距离都是1,如果正方形ABCD的四个顶点分别在四条直线上,则sinα=(  )

如图,已知直线l1∥l2∥l3∥l4,相邻两条平行直线间的距离都是1,如果正方形ABCD的四个顶点分别在四条直线上,则sinα=(  )

#如图,已知直线l1∥l2∥l3∥l4,相邻两条平行直线间的距离都是1,如果正方形ABCD的四个顶点分别在四条直线上,则sinα=(  )| 来源: 网络整理| 查看: 265

在20世纪80年代,由于弃农从商现象盛行,导致大片耕地落荒,杂草丛生,但现在已有许多地方在杂草丛生之地展开了多种形式的立体农业,收获颇丰.常见的实例就是果树﹣草菇结构农林生态系统,如在苹果树下进行了间种草菇,利用高湿度、低风速等环境条件,获得了良好的经济效益.请回答有关问题.

(1)耕地落荒后逐渐形成的演替类型应为   .人类的活动往往会使群落演替按照不同于自然演替的   进行.立体农业是运用了群落的   原理,为充分利用空间和资源而发展起来的一种农业生产模式.

(2)苹果树开花后,为提高单果的重量,可喷施较高浓度的   疏花疏果.

(3)若果树﹣菇结构农林生态系统中的果树只有一种,则果树种群数量的最基本特征是   .若该系统内有大量某种害虫侵蚀果树的叶片,我们可以利用人工合成的性引诱剂诱杀害虫的雄性个体,破坏害虫种群正常的   ,就会使很多雌性个体不能完成交配,结果直接影响害虫的   ,从而减少害虫种群的数量.

(4)草菇在该生态系统中属于   ,苹果树落下的叶子可为草菇提供营养,栽培草菇剩下的基质又可被果树根系吸收利用.这种生产模式体现了生态系统的   功能.

解:(1)耕地落荒后逐渐形成的演替类型应为次生演替.人类的活动往往会使群落演替按照不同于自然演替的速度和方向进行.立体农业是运用了群落的空间结构原理,为充分利用空间和资源而发展起来的一种农业生产模式.

(2)生长素的生理作用具有两重性,低浓度促进生长,高浓度抑制生长,苹果树开花后,为提高单果的重量,可喷施较高浓度的生长素类似物疏花疏果.

(3)若果树﹣菇结构农林生态系统中的果树只有一种,则果树种群数量的最基本特征是种群密度若该系统内有大量某种害虫侵蚀果树的叶片,我们可以利用人工合成的性引诱剂诱杀害虫的雄性个体,破坏害虫种群正常的性别比例,就会使很多雌性个体不能完成交配,结果直接影响害虫的出生率,从而减少害虫种群的数量.

(4)草菇在该生态系统中属于分解者,苹果树落下的叶子可为草菇提供营养,栽培草菇剩下的基质又可被果树根系吸收利用.这种生产模式体现了生态系统的物质循环或物质循环和能量流动的功能.

故答案为:

(1)次生演替 速度和方向 空间结构

(2)生长素类似物

(3)种群密度 性别比例 出生率

(4)分解者 物质循环或物质循环和能量流动

已知两对等位基因A和a、B和b分别位于两对同源染色体上,现用两纯合亲本(AABB、aabb)进行杂交,产生的F1再自交产生F2,请分析回答:

(1)若单独观察分析一对相对性状的遗传特点,F1只出现显性性状,F1自交的后代中出现显性和隐性两种性状,这种现象遗传学上叫做   .

(2)同时观察分析两对性状的遗传特点,符合基因的   定律.若两对等位基因分别控制两对相对性状,则F2的双显性个体中杂合体占   ,若选取F2中的两个杂合体杂交,其子代只有一种表现型,则这两个杂合体的基因型是   .

(3)若两对等位基因控制一对相对性状,且只要存在一个显性基因,个体便表现为显性,则F2中显性性状与隐性性状的比例为   .若只有A、B同时存在时,个体才表现出显性,则F1与双隐性个体杂交,子代中隐性个体占   .

(4)若两对等位基因共同控制着植株的高度,且以累加效应决定植株的高度,每个显性基因的遗传效应相同.纯合子AABB高50cm,aabb高30cm,它们之间杂交得到F1后,再自交得到F2,如果忽略环境因素的影响,则F2中表现为40cm高度的个体的基因型有   .

解:(1)若单独观察分析一对相对性状的遗传特点,F1只出现显性性状,F1自交的后代中出现显性和隐性两种性状,这种现象遗传学上叫性状分离.

(2)由于两对等位基因A和a,B和b分别位于两对同源染色体上,所以同时观察分析两对性状的遗传特点,符合基因的自由组合定律.若两对等位基因分别控制两对相对性状,则F2的双显性个体占[0d9079380cdb4657.png],其中纯合体占[6794e8b12ee42bfb.png],杂合体占[d97786c20998f512.png].若选取F2中的两个杂合体杂交,其子代只有一种表现型,则这两个杂合体的基因型是AABb×AaBB.

(3)若两对等位基因控制一对相对性状,且只要存在一个显性基因,个体便表现为显性,说明只有纯隐性个体才表现为隐性.因此,F2中显性性状与隐性性状的比例为(A_B_、A_bb、aaB_):aabb=15:1.若只有A、B同时存在时,个体才表现为显性,则F1AaBb与双隐形个体aabb杂交,子代中的基因型有AaBb、Aabb、aaBb、aabb,所以隐性个体所占比例为[536f8e7533f80dbc.png].

(4)基因型为AABB和aabb的两株植物杂交,F1的基因型为AaBb,又由于基因以累加效应决定植株的高度,且每个显性基因的遗传效应是相同的,纯合子AABB高50cm,aabb高30cm,即植株的高度与显性基因的个数呈正相关,每增加一个显性基因,植株增高(50cm﹣30cm)÷4=5cm.AABB和aabb杂交得到F1后,再自交得到F2,如果忽略环境因素的影响,则F2中表现为40cm高度的个体含有两个显性基因,所以基因型为AAbb、aaBB、AaBb.

故答案为:

(1)性状分离

(2)自由组合 [01e328b365de22df.png] AABb×AaBB

(3)15:1 [d4e88d6e973428ce.png]

(4)AAbb、aaBB、AaBb

秸秆野外焚烧会污染环境,微生物降解技术能使秸秆尽快腐烂增加土壤肥力,利用其生产燃料乙醇,也可以变废为宝.回答下列有关问题:

(1)秸秆的主要成分是纤维素,可构成植物细胞的   .

(2)能分解纤维素的微生物包括细菌、真菌等,它们大多数能合成纤维素酶,将纤维素分解成纤维二糖,进一步分解成葡萄糖.纤维素酶是一种复合酶,一般认为它至少包括三种组分,即   、   和   .

(3)从土壤中分离分解纤维素的微生物的实验流程如下:①土壤取样→②选择培养→③梯度稀释→④将样品涂布到鉴别培养基上→⑤挑选菌落.该过程中步骤②选择培养基的营养物质的特点是   ,步骤③中稀释的目的是   .

(4)用稀释涂布平板法测定土壤样品中纤维素分解菌数量.从稀释倍数为106倍的培养液中各取0.2mL稀释液分别涂布了三个平板,统计得到三个平板上的菌落数分别是210、240和246个,则每毫升原样液中的菌体数是   个,用这种方法测得的菌体数可能比实际活菌数   .

解:(1)纤维素是构成植物细胞壁的主要成分,其单体为葡萄糖.

(2)纤维素的分解需要纤维素酶,纤维素酶是一种复合酶,一般认为它至少包括三种组分,即C1酶、Cx酶和葡萄糖苷酶,前两种酶使纤维素分解成纤维二塘.

(3)该培养基从物理性质来看属于固体培养基;该过程中步骤②选择培养基的营养物质的特点是以纤维素作为唯一碳源,步骤③中稀释的目的是便于形成单个的菌落.

(4)按照该同学的结果,每克样品中的菌落数=平板上菌落数的平均值÷体积×稀释倍数=(210+240+246)÷3÷0.2×106=1.165×109.当两个或多个细胞连在一起时,平板上观察的是一个菌落,因此用这种方法测得的菌体数比实际活菌数量少.

故答案为:

(1)细胞壁

(2)C1酶 CX酶 葡萄糖苷酶

(3)以纤维素作为唯一碳源 便于形成单个的菌落

(4)116×107个 少 涂布时,当两个或多个细菌连在一起时,平板上观察的是一个菌落

通过胚胎工程可以挖掘动物的繁殖潜力,为优良牲畜的大量繁殖提供有效的解决办法.某研究机构运用生物工程技术,通过让普通家兔***的方法,繁育良种肉用兔,主要技术流程如图所示,据图回答下列相关问题:

(1)诱导超数排卵用到的激素是   ,步骤甲为   ,收集到的精子要进行   处理.

(2)早期胚胎培养用到的培养液成分中,除了一些无机盐和有机盐类外,还需添加维生素、激素、氨基酸、核苷酸等营养成分以及   等物质.

(3)在繁育过程中,出现了一只体型特别大的良种肉用兔,若要快速地大量繁殖出同样大体型的个体,可采用的技术是   .采用这一技术时,需要使用   的   方法使供体细胞与去核卵母细胞融合,构建重组胚胎,然后将胚胎移入受体家兔体内.该技术与胚胎工程技术都涉及胚胎的移植受体对移入子宫的外来胚胎基本上不发生   反应,这为胚胎在受体内的存活提供了可能.进行胚胎移植的优势是   .

解:(1)给母畜注射促性腺激素可促使其超数排卵;步骤甲为体外受精;收集到的精子要进行获能处理.

(2)早期胚胎培养用到的培养液成分中,除了一些无机盐和有机盐类外,还需添加维生素、激素、氨基酸、核苷酸等营养成分以及动物血清等物质.

(3)要快速地大量繁殖出同样大体型的个体,可采用核移植技术.采用这一技术时,需要使用病毒介导或电脉冲(或电刺激)方法使供体细胞与去核卵母细胞融合,构建重组胚胎,然后将胚胎移入受体家兔体内.该技术与胚胎工程技术都涉及胚胎的移植受体对移入子宫的外来胚胎基本上不发生免疫排斥反应,这为胚胎在受体内的存活提供了可能.进行胚胎移植的优势是可充分发挥优秀个体的繁殖潜力.

故答案为:

(1)促性腺激素 体外受精 获能

(2)动物血清

(3)核移植 病毒介导 电脉冲(或电刺激) 免疫排斥 可充分发挥优秀个体的繁殖潜力

(10分)假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下便条.便条中共有10处语言错误,每句中最多有两处.错误涉及一个单词的增加、删除或修改.

增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词.

删除:把多余的词用斜线\划掉.

修改:在错的词下画一横线,并在该词下面写出修改后的词.

注意:

1. 每处错误及其修改均仅限一词;

2.只允许修改10处,多者(从第11处起)不计分.

Among all the European cities, I love Paris more. Paris is known to the world center of culture and fashion. You may find many famous museums there, the most famous of that is Louvre.

Louvre dated back to the 12th century, which used to be a royal palace. It is said that it has a collection of roughly 400 thousand of art works, paintings and sculptures including. In front of museum is a glass pyramid designed by Bei Yuming. Whatever makes Louvre world famous is Da Vinci's Mona Lisa.

It is a pity that not all the collections are openly to the public, and Louvre is well worth paying a visit to.

Among all the European cities, I love Paris more. Paris is known to the world center of culture and fashion. You may find many famous museums there, the most famous of that is Louvre.

Louvre dated back to the 12th century, which used to be a royal palace. It is said that it has a collection of roughly 400 thousand of art works, paintings and sculptures including. In front of∧ museum is a glass pyramid designed by Bei Yuming. Whatever makes Louvre world famous is Da Vinci's Mona Lisa.

It is a pity that not all the collections are openly to the public, and Louvre is well worth paying a visit to.

详解;

1.more改为most. 考查最高级.根据范围among all the cities, 我应该最喜欢巴黎,所以用最高级.

2. to改为as.考查固定短语.be famous as是固定短语"以…而出名",根据句意以世界的时尚中心而出名.

3. that改为which.考查定语从句.本句是非限制性定语从句,而且在定语从句中介词后边的关系代词用which.

4. dated改为dates.考查时态.卢浮宫追溯到12世界应该用一般现在时,所以用dates.

5. of去掉. 考查数词.400千,thousand与具体数字连用不能有of.thousands of是数千个.

6.including改成included.考查形容词.included是形容词"包括在内的",including是介词.本句用形容词做后置定语.

7. museum前面加the.考查冠词.这里特指在这个博物馆的前边,所以用定冠词the.

8. Whatever改成What.考查主语从句.本句是主语从句,从句﹣﹣makes Louvre world famous 中缺少主语,使卢浮宫闻名世界的是达芬奇的蒙娜丽莎.所以用what引导.

9. openly改成open.考查固定短语.be open to是固定短语"对…开放".

10. and改成but.考查连词.根据句意:遗憾的是,并非所有藏品都向公众开放,但卢浮宫值得一游.两句之间是转折关系,所以用but引导.

(25分)假设你是李华,新年来临,校学生会拟举行英语歌曲大赛.请你以学生会的名义在英语校报上刊登一则通知.要点如下:

1.比赛的目的与内容;

2.时间与地点:下周六下午三点到五点,校体育馆;

3.其他信息(报名方式与截止时间等);

4.欢迎踊跃参加.

注意:1. 词数100左右;

2. 可以适当增加细节,以使行文连贯.

3. 题目和结尾已经给出.

Notice

﹣﹣﹣﹣﹣﹣﹣﹣﹣

Students' Union

Notice

The New Year is coming. In order to make our school life more colorful and help relax ourselves in the busy school life,the student union is going to hold an English song contest. 【高分句型一】(目的)Competition will be held on the school gymnasium from 3:00 PM to 5:00 PM on next Saturday.(时间地点)

All classes of Senior Three are expected to take an active part and it is hoped that all of the students will make good preparations.【高分句型二】 Besides,students are required to gather on the playground having on their uniforms.The judges will be made up of experts and students.Prizes will be given according to the total scores of the classes.We'll choose the first six classes as the winners.For any questions,call Li Hua at 44858476.(其他信息)

Please be on time.Hope you can enjoy it.(欢迎踊跃参加)

Students' Union

(10分)假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文.文中共有10处语言错误,每句中最多有两处.每处错误仅涉及一个单词的增加、删除或修改.

增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词.

删除:把多余的词用斜线(\)划掉.

修改:在错的词下画一横线,并在该词下面写出修改后的词.

注意:1.每处错误及其修改均仅限一词;

As is often the case,when people are attending meeting,having meals or waiting buses,you can always find them addicted to their phones,complete ignoring others.

This is really a common phenomenon in our life.The reason is why smart phones nowadays can be used for people to play mobile games and kept in touch with friends through QQ and WeChat.Besides,too much exposure to phones are bad for people in terms of health.Moreover,people involved in phones fail to communicate good with those around them.

As far as I am concerning,people should wisely make use of their phones to help with their work and study.Meanwhile,care most about their family and friends rather than mobile phones.

As is often the case,when people are attending meeting,having meals or waiting∧buses,you can always find them addicted to their phones,complete ignoring others.

This is really a common phenomenon in our life.The reason is why smart phones nowadays can be used for people to play mobile games and keptin touch with friends through QQ and WeChat.Besides,too much exposure to phones are bad for people in terms of health.Moreover,people involved in phones fail to communicate goodwith those around them.

As far as I am concerning,people should wisely make use of their phones to help with their work and study.Meanwhile,care most about their family and friends rather than mobile phones.

详解:

1.meeting改为meetings;考查名词复数,meeting是可数名词,根据句意,此处应该用复数形式,

2.waiting后面加for;考查介词,wait意为"等待",是不及物动词后面跟宾语时要加介词for.

3.complete改为completely;考查副词,此处用副词作状语,修饰动词ignoring.

4.why改为that;考查表语从句,分析句子结构可知,这里用that引导一个从句,作系动词is的表语.

5.kept改为keep;考查并列结构,分析句子结构可知,这里and连接并列结构,并列成分为play mobile games 和keepin touch with friends,前面有不定式to,所以了这两个动词都应该用动词原形.

6.Besides改为However;考查连词,结合上下文分析,句意为"然而,过多的暴露在手机面前对健康是有害的",所以这里要用However表示转折关系.

7.are改为is;考查主谓一致,分析句子结构可知,句子的主语为too much exposure,故系动词要用单数形式is.

8.good改为well;考查副词,此处用副词作状语,修饰动词communicate.

9.concerning改为concerned;考查固定结构,be concerned是固定搭配,意为"就…而言",文中As far as I am concerned意为"就我个人而言".

10.most改为more;考查比较级,结合句意"多关心一下身边的亲人和朋友,而不是手机"可知这里应该用比较级形式,与后面的mobile phones.

(25分)假定你是李华,最近你在当地报纸上看到一则游泳培训班的广告,称其有称职教练( instructor),一周包会.你会一点游泳,但水性不太好,想在暑假参加训练.请你写一封咨询信了解相关情况,要点如下:

1.训练的具体时间和地点.

2.条件和费用.

3.其他特别注意的事项.

注意

1.词数 100 左右.

2.可以适当增加细节,以使行文连贯.

3.开头语和结束语已为你写好.

Dear Sir/Madam,

I have read your advertisement in the newspaper.

   

I am looking forward to hearing from you soon.

Yours sincerely,Li Hua.

Dear Sir/Madam

I have read your advertisement in the newspaper.You mentioned in it that your instructors are fully qualified and you ensure that learners will be able to swim well after one week's training.

I can swim a little but I'm not very confident in the water.So I'm interested in taking part in the training course.Fortunately,the summer holiday is around the corner.I'm writing to inquire when and where the course will be given,and how long the training course will last each day.

I also want to know how much you will charge me for that.

Besides,would you be so kind as to tell me whether there is anything special that should be prepared or does your company provide everything necessary?

I am looking forward to hearing from you soon.

Yours sincerely,

Li Hua

(10分)假定英语课上老师要求同桌之间交换修改作文,请你修改你同桌写的以下作文.文中共有 10

处错误,每句中最多有两处.每处错误仅涉及一个单词的增加、删除或修改. 增加:在缺词处加一个漏词符号(^),并在此符号下面写出该加的词. 删除:把多余的词用斜线(\)划掉. 修改:在错的词下划一横线,并在该词下面写出修改后的词. 注意:1.每处错误及其修改均仅限一词;

2.只允许修改 10 处,多者(从第 11 处起)不计分.

Knowing how to do in case of fire is important. If the fire broke out, what would you do? First, you should warn everyone in the building about the danger. Don't panic or start shouting. Be calmly and act quickly. Second, you and all the others should be get out of the building. Don't stop take anything with you. Once you are out of the building, stay out. Do not go back for some reason. Finally, when you are out of the building, called the fire police. Don't try to put off the fire yourself, that can be dangerous if you do so.

Knowing how to do in case of fire is important. If the fire broke out, what would you do? First, you should warn everyone in the building about the danger. Don't panic or start shouting. Be calmly and act quickly. Second, you and all the others should be get out of the building. Don't stop∧ take anything with you. Once you are out of the building, stay out. Do not go back for some reason. Finally, when you are out of the building, called the fire police. Don't try to put off the fire yourself, that can be dangerous if you do so

详解;

1.how 改为 what,考查特殊疑问词,表示做什么,所以用what+不定式.

2. the 改为 a,考查冠词,泛指一个,所以用不定冠词.

3.about 改为 of,考查固定搭配,warn sb of sth警告某人小心某事.

4. calmly 改为 calm,考查形容词,作表语,所以用形容词.

5. 删掉 be (get 之前),考查句子结构,should get out of作谓语,be多余.

6. stop 后加 to,考查不定式,stop to do停下来去做.

7. some 改为 any,考查词义辨析,表示"任何一个"用any.some表示"一些",用于肯定句,any表示"一些"用于否定句、疑问句.

8. calling 改为 call,考查祈使句,when引导时间状语从句,主句用祈使句,所以用动词原形开头.

9. off 改为 out,考查固定搭配,put off推迟;put out熄灭.

10. that 改为 which,考查非限制性定语从句,指代前面句子,在非限制性定语从句中作主语,所以用which引导.

(25分)假如你是李华.你的英国笔友 Tom 来信说他最近沉溺于一个电脑游戏,经常玩到通宵,现在 发现视力下降、头痛等身体不适的症状.请你根据以上的提示给 Tom 写封信,劝说他少玩电脑游 戏,培养其他健康的爱好.

要求:1.词数 100 词左右; 2. 可适当增加细节,以使行文连贯.

Dear Tom ,

Yours,

Li Hua

Dear Tom,

I am sorry to hear from you that your eyesight is becoming worse and worse and you also have a headache these days. From your letter, I know all these health problems result from your spending too much time playing computer games.(了解对方的情况)

As we know, when we are very bored, tired or stressed, computer games are a good source of enjoyment. 【高分句型一】However, they also have negative effects on us. If you are addicted to computer games, your eyesight and your health will suffer more. Moreover, your school work will get worse, which I think is the most important for you right now.【高分句型二】 So why not try some healthy things, such as swimming and climbing?(劝说他少玩电脑游 戏,培养其他健康的爱好)

I hope my suggestions will be of help to you. I am looking forward to your good news.(表达愿望)

Yours,

Li Hua



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