试题与答案

某校实验小组探究“甲状腺激素对蝌蚪生长发育的影响”的实验过程如下: 取两个相同的

题型:解答题

题目:

某校实验小组探究“甲状腺激素对蝌蚪生长发育的影响”的实验过程如下:

取两个相同的玻璃缸,分别贴上标签A、B

实验步骤A缸B缸
1000mL池塘水1000mL自来水
分别加入同时期孵化出的蝌蚪各1只
加入等量的蝌蚪饲料
加少许甲状腺激素制剂不加甲状腺激素制剂
水温保持在适宜的范围内
每天记录蝌蚪生长发育的情况.请回答:

(1)在这个实验设计中,有两个步骤不够严谨,请你加以改进完善:

______;______.

(2)在A缸中加入少许甲状腺激素制剂,而B缸内不加,其目的是______.

(3)如果实验按你修改后的方案进行,预期的实验结果是______.该实验所得出的结论是______.

答案:

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题型:阅读理解

阅读理解。

     A year ago August, Dave Fuss lost his job driving a truck for a small company in west Michigan. His

wife, Gerrie, was still working in the local school cafeteria, but work for Dave was scarce, and the price

of everything was rising. The Fusses were at risk of joining the millions of Americans who have lost their

homes in recent years. Then Dave and Gerrie received a timely gift-$7,000, a legacy (遗产) form their

neighbors Ish and Arlene Hatch, who died in an accident. "It really made a difference when we were going

under financially." says Dave.

     But the Fusses weren't the only folks in Alto and the neighboring town of Lowell to receive unexpected

legacy from the Hatches. Doxens of other families were touched by the Hatches' generosity. In some cases,

it was a few thousand dollars; in other, it was more than $100,000.

     It surprised nearly everyone that the Hatches had so much money, more than $3 million-they were an

elderly couple who lived in an old house on what was left of the family farm.

     Children of the Great Depression, Ish and Arlene were known for their habit of saving. They thrived own

(喜欢) comparison shopping and would routinely go from store to store, checking prices before making a

new purchase.

     Through the years, the Hatches paid for local children to attend summer camp when their parents couldn't

afford it. "Ish and Arlene never asked you needed anything," says their friend Sand Van Weelden, "They could

see things they could do go make you happier, and they would do them."

     Even more extraordinary was that the Hatches had their farmland distributed. It was the Hatches' wish that

their legacy-a legacy of kindness as much as one of dollars and cent-should enrich the whole community (社

区) and Ish and Arlene Hatch's story. Neighbors helping neighbors-that was Ish and Arlene Hatch's story.

1. According to the text, the Fusses _____.

A. were employed by a truck company

B. were in financial difficulty

C. worked in a school cafeteria

D. lost their home

2. Which of the following is true of the Hatches?

A. They had their children during the Great Depression

B. They left the family farm to live in an old house

C. They gave away their possessions to their neighbors

D. They helped their neighbors to find jobs

3. Why would the Hatches routinely go from store?

A. They decided to open a store

B. They wanted to save money

C. They couldn't afford expensive things

D. They wanted to buy gifts for local kids

4. According to Sand Van Weelden, the Hatches were _____.

A. understanding

B. optimistic

C. childlike

D. curious

5. What can we learn from the text?

A. The community of Alto was poor

B. The summer camp was attractive to the parents

C. Sandy Van Weelden got a legacy form the Hatches

D. The Hatches would like the neighbors to follow their example

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