21.请在图7甲中画出对应入射光线的反射光线并标出反射角,请根据透镜对光线的作用 规律.在图7乙的方框中填入一个合适的透镜. 查看更多

 

题目列表(包括答案和解析)

(11分)下图甲、乙分别表示我国医学工作者自主研制SARS灭活疫苗过程中,某志愿者接种疫苗后两周内体温和抗体浓度的变化。请据图回答下列问题

(1)注射疫苗后,志愿者出现轻度发热现象,调节机体产热的激素主要有          
                      ,维持体温恒定的调节方式是                      调节,
体温调节中枢是______________。
(2)若该志愿者注射疫苗后的第15天感染SARS病毒,请在乙图中画出其体内抗体变化曲线。抗体的本质是_________,由_____________直接产生,抗体合成及分泌的途径是________________________________________________________(2分) 。
(3)研究发现SARS病毒的增殖需要逆转录酶,说明SARS病毒的遗传物质是       
;从遗传物质分析,研制SARS疫苗困难的主要原因是                             

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有如下图所示的探究性实验装置共6个,6个装置中分别加入葡萄糖饱和溶液和两个凝胶珠,实验开始时,小液滴都在c点(刻度管足够长,瓶内氧气充足)。6个装置分别置于0℃、15℃、25℃、35℃、45℃、55℃温度下10分钟后记录各个装置中的小液滴位置,并描绘出坐标曲线图(如甲曲线)

(1)实验的目的是                                ,自变量是                
(2)瓶中氢氧化钠溶液的作用是          ,小液滴移动的距离表示         
(3)实践上如果通过固定化醋酸菌生产醋酸,那么制备的凝胶珠大小与固定化酵母菌生产酒精相比,应该注意什么问题?为什么?
(4)如果制备固定化醋酸菌细胞实验中,海藻酸钠浓度过低,请在坐标系中画出实验开始10分钟后的曲线乙。
(5)工业生产中利用固定化细胞技术进行生产,从哪些方面可以达到延长利用固定化细胞的时间(至少两点)?

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听力测试(20分)

Ⅰ.根据所听到的答语,填写下列句中所缺的疑问词。(5分)

1.________ ________ does your first class start?

2.________ is the oldest in your family?

3.________ does your brother do?

4.________ are they?

5.________ are you late for school?

Ⅱ.听句子,选出与你所听到的句子意思相近的选项。(5分)

1.

A.Mike goes to school every day.

B.Mike gets up at seven in the morning.

C.Mike goes to school in the morning.He comes home in the afternoon.

D.Mike has lunch at home every day.

2.

A.I usually do morning exercises at six in the morning.

B.I usually get up at six in the morning.

C.I don't usually get up at six in the morning.

D.I usually watch TV at six in the evening.

3.

A.Jim is very busy.

B.John

is very busy.

C.Jim isn't very busy.

D.Jim is very busy.John is very busy, too.

4.

A.We have breakfast at 7∶40.

B.We have breakfast at about 7∶40.

C.We have dinner at 7∶40.

D.We have dinner at about 7∶40.

5.

A.Mr.Brown can speak Chinese well.

B.Mr.Brown can't speak Chinese.

C.Mr.Brown can speak Chinese, but not very much.

D.Mrs.Brown can speak Chinese.

Ⅲ.根据句子或对话内容选择适当的图画回答所提出的问题。(5分)

1.What time is the plane?

2.What time is the train?

3.What time is it now?

4.What time is the flight to London?

5.What time is the next bus?

Ⅳ.听对话,根据你所听到的内容在下面每幅图的时钟上画出时针和分针。(5分)

1.

2.

3.

4.

5.

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图1所示传送带上有一个物体M,质量为2kg ,它与传送带一起以lm/s的速度在水平方向向右匀速运动,不计空气阻力.请在图1中画出M受力的示意图.

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图1所示传送带上有一个物体M,质量为2kg ,它与传送带一起以lm/s的速度在水平方向向右匀速运动,不计空气阻力.请在图1中画出M受力的示意图.

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