问题 单项选择题

下图表示某物种迁入新环境后,种群增长速率随时间的变化关系,下列有关叙述,不正确的是()

A.第10年后,该种群的数量开始下降

B.经调查该种群在第10年时个体数量为n,估算该种群在此环境中的环境负荷量约为2n

C.该种群在20年内呈“S”型增长

D.经调查该种群在第20年时的出生率为m,估算种群在此环境中的死亡率为m

答案

参考答案:A

解析:10到15年,种群增长速率仍然大于0,种群数量一直增长;A错误。K/2,时种群增长速率最大,图示的第10年时种群增长速率最大,由此可知该种群在此环境中的环境负荷量约为2n;B正确。20年内,种群增长速率先增大后减小最后为0,由此可推知该种群在20年内呈“S”型增长;C正确。20年时种群数量达到环境的最大容纳量,此时种群增长速率=0,由此可推知在该年份(若不考虑其它因素对种群数量的影响),种群的出生率=死亡率;D正确。考点:本题考查种群数量的变化,意在考查结合图示信息,运用所学知识与观点,通过比较、分析与综合等方法对某些生物学问题进行解释、推理,做出合理的判断或得出正确的结论的能力。

阅读理解

阅读理解。

     Whoever has made a voyage up the Hudson River must remember the Catskill Mountains. They are a

branch of the great Appalachian family, and can be seen to the west rising up to a noble height and towering

over the surrounding country. When the weather is fair and settled, they are clothed in blue and purple, and

print their beautiful shapes on the clear evening sky, but sometimes when it is cloudless, gray steam gathers

around the top of the mountains which, in the last rays of the setting sun, will shine and light up like a crown

of glory (华丽的皇冠).

     At the foot of these mountains, a traveler may see light smoke going up from a village.

     In that village, and in one of the houses (which, to tell the exact truth, was sadly time-worn and weather-

beaten), there lived many years ago, a simple, good-natured fellow by the name of Rip Van Winkle.

     Rip's great weakness was a natural dislike of all kinds of money-making labor. It could not be from lack

of diligence (勤劳), for he could sit all day on a wet rock and fish without saying a word, even though he

was not encouraged by a single bite. He would carry a gun on his shoulder for hours, walking through woods

and fields to shoot a few birds or squirrels. He would never refuse to help a neighbor, even in the roughest

work. The women of the village, too, used to employ him to do such little jobs as their less helpful husbands

would not do for them. In a word, Rip was ready to attend to everybody's business but his own.

     If left to himself, he would have whistled ( 吹口哨) life away in perfect satisfaction; but his wife was

always mad at him for his idleness (懒散). Morning, noon, and night, her tongue was endlessly going, so that

he was forced to escape to the outside of the house-the only side which, in truth, belongs to a henpecked

husband.

1. Which of the following best describes the Catskill Mountains?

A. They are on the west of the Hudson River.

B. They are very high and beautiful in this area.

C. They can be seen from the Appalachian family.

D. They gather beautiful clouds in blue and purple.

2. The hero of the story is probably _____.

A. hard-working and likes all kinds of work

B. idle and hates all kinds of jobs

C. simple, idle but very dutiful

D. gentle, helpful but a little idle

3. The underlined words "henpecked husband" in the last paragraph probably means a man who _____.

A. likes hunting

B. is afraid of hens

C. loves his wife

D. is afraid of his wife

4. What would be the best title for the text?

A. Catskill Mountains.

B. A Mountain Village.

C. Rip Van Winkle.

D. A Dutiful Husband.

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