题目内容

家蝇对拟除虫菊酯类杀虫剂产生抗性，原因是神经细胞膜上某通道蛋白中的一个亮氨酸替换为苯丙氨酸。下表是对某市不同地区家蝇种群的敏感性和抗性基因型频率调查分析的结果。下列叙述正确的是（）

A. 上述通道蛋白中氨基酸的改变是基因碱基对缺失的结果
B. 甲地区家蝇种群中抗性基因频率为22%
C. 比较三地区抗性基因频率可知乙地区抗性基因突变率最高
D. 丙地区敏感性基因频率高是自然选择的结果

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12.(20分）超导现象是20世纪人类重大发现之一，日前我国己研制出世界传输电流最大的高温超导电缆并成功示范运行。 (l）超导体在温度特别低时电阻可以降到几乎为零，这种性质可以通过实验研究．将一个闭合超导金属圈环水平放置在匀强磁场中，磁感线垂直于圈环平面向上，逐渐降低温度使环发生由正常态到超导态的转变后突然撤去磁场，若此后环中的电流不随时间变化．则表明其电阻为零。请指出自上往下看环中电流方向，并说明理由。

下列有关元素的性质及其底边规律正确的是

A. IA族与VIIA族元素间可形成共价化合物或离子化合物
B. 最高第二周期元素从左到右，正价从+1递增到+7
C. 同主族元素的简单阴离子还原性越强，水解程度越大
D. 同周期金属元素的化合价越高，其原子失电子能力越强

(以下试题六至试题八任选一题)阅读下列说明和C++代码，请回答问题1至问题3。【说明】已知下列程序运行时的输出应为：1:11:11:1【C++程序】01 #include ＜iostream＞02 using namespace std;03 class Stock{04 protect:05 (1) {};06 Stock(iht n, int pr=1){07 shares = n; share_val=pr;08 };09 void～Stock(){};10 public:11 //成员函数12 void output(){13 (2) ＜＜ shares ＜＜ ":" ＜＜ share val ＜＜ endl;14 }15 private:16 //成员变量17 int shares;18 int share_val;19 };2021 void main(){22 Stock a(1); a.output();23 Stock b; b.output();24 Stock c = Stock(); c.output();25 } 【问题2】类Stock的定义中有两处错误，请指出错误所在行号并给出该行修改后的完整结果。

New Zealand Immigration Service (NZIS) introduces the Student Bank Loan Scheme to facilitate easier processing of student visa applications from Chinese people who want to go to New Zealand. It will make it easier for applicants or their parents to prove their financial ability to support the intended duration of study in NZ. Step 1: Applicants (or their parents) will apply for a loan to CIB directly. Step 2: CIB then considers the application for a loan. CIB requires deposits in the bank to be frozen and that they are at least 10% larger than the loan amount required. Step 3: If the loan is approved, CIB will then issue an ’Advice for Study Loan Abroad’ document to the applicant or their parents. Step 4: The applicant then lodges their visa application at the New Zealand Immigration Service (NZIS) together with their ’Advice for Study Loan Abroad’ document.Step 5: The NZIS processes the application (which may include verification of the ’Advice for Study Loan Abroad’ document) and if satisfied will notify the applicant that they have been approved-in-principle. Step 6: The applicant takes this notification to the bank and completes a special application form to activate the loan. CIB will then issue a ’Certificate of Credibility. Personal Loan for Study Abroad’ document, showing that the loan has been activated. Step 7: The applicant submits this document, together with the any other approval-in-principle requirements to NZIS, who then finalizes the application. Step 8: If the applicant completes their study in NZ before the duration of their loan, they contact the NZIS to get a letter saying that they have completed their study. NZIS will then issue a letter which the applicant then takes to CIB to release their funds.The following steps explain the operational procedures for the use of bank loan. A. Students apply to CIBB. CIB considers the Bank LoanC. CIB issues ‘Advice for Study Loan Abroad’ if loan approved D. Students lodge applications to NZISE. NZIS processes applicationsF. Students go to CIB to activate bank loan if applications approved G. Students provide ‘’Certificate of Credibility. Personal Loan for Study Abroad’ to NZIS to have their visa labels issued H. Students contact NZIS when course completed. If the loan is approved, NZIS will then issue an ’Advice for Study Loan Abroad’ document to the applicant or their parents.

A. 对
B. 错