某同学在观察自制淡水生物装片时,结合所学的知识绘图如下图所示。请分析回答: (1

题型:读图填空题

问题:

某同学在观察自制淡水生物装片时,结合所学的知识绘图如下图所示。请分析回答:

(1)控制细胞内外物质交换的结构是[    ]_________。

(2)该细胞进行新陈代谢的主要场所是[    ]_________。

(3)水生生物必须随水环境的变化及时调整渗透压,与调节细胞渗透压大小有关的主要结构是[    ]_____。

(4)若该细胞进行有丝分裂,结构[7]的作用是______________。

(5)综合上述分析,该同学绘制的最可能是___________细胞。

考点:各种细胞器的结构和功能细胞膜的功能
题型:读图填空题

下列各组词语中,汉字书写完全正确的一项是(    )(3分)

A.倘佯聒噪糟蹋庶竭弩钝

B.作揖箫索恣睢东施效颦

C.呕气拮据嗽口一蹴而就

D.窘迫振奋忐忑歇斯底里

题型:读图填空题

A single pipeline ___________ all the houses with water.

A.is served

B.serves

C.are serving

D.serve

题型:读图填空题

植物对昼夜温度交替变化的反应称为物候节律。()

题型:读图填空题

某分部工程划分为4个施工过程、3个施工段,组织加快的成倍节拍流水施工,如果流水节拍分别为6、4、4、2天,则流水步距为( )天。

A.1
B.2
C.4
D.6

题型:读图填空题

With unemployment rising and housing costs still high, cities around the country are experiencing a new and sudden wave of homelessness. Shelters are overflowing, and more people this year are sleeping on floors in dingy social service centers, living in cars or spending nights on the streets.

In New York, Boston and other cities, homelessness is at record levels, a consequence of a faltering (摇晃的) economy that has crumbled even further after the Sept.11 attacks.

A survey by the U. S. Conference of Mayors released last week found that requests for emergency shelter in 27 cities had increased an average of 13 percent over last year. The report said the increases were 26 percent in Trenton; 25 percent in Kansas City, Mo.; 22 percent in Chicago; 20 percent in Denver; and 20 percent in New Orleans.

An unusual confluence of factors seems to be responsible for the surge. Housing prices, which soared in the expansion of the 1990’s, have not gone down, even though the economy has tumbled. A stream of layoffs has newly unemployed people taking low-wage jobs that might have otherwise gone to the poor. Benefits for welfare recipients are expiring under government-imposed deadlines. And charitable donations to programs that help the disadvantaged are down considerably, officials around the country said, because of the economy and the outpouring of donations for people affected by Sept.11.

"This is an unprecedented convergence (集中) of calamities (灾难), " said Xavier De Souza Briggs, an assistant professor of public policy at the John F. Kennedy School of Government at Harvard. "It’s really a crisis. "

More than half the cities surveyed by the mayors’ group reported that in the last year people had remained homeless longer, an average of six months.

There is no total number for the homeless nationwide. Experts said it was difficult to compare the situation with statistics in previous decades, because counting methods have improved. Yet, several experts said they believed that the increases reported by cities like Boston and Chicago reflected a national trend.

"My impression is there is more homelessness now than there was 20 years ago, " Gary Burtless, an economist at the Brookings Institution, said, adding that he believed that economic factors were not the sole explanation.

"I think that there must be a greater segment of our population that has tenuous connections to family and friends, and therefore has fewer resources to fall back on when something very bad happens like when they lose their job, " he said.

According to economist Gary Burtless, What factor accounts for the surge of homeless apart from the economic explanation().

A. Political.

B. Social.

C. Religious.

D. International.

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