(二)Some spiders hunt on the ground, others

题型:单项选择题

问题:

(二)

Some spiders hunt on the ground, others build webs to trap their food, but the grass water spider catches its prey by running along the surface of the water.

This special water spider lives on the grassy banks of streams where mosquitoes, damsel flies and other insects come to feed and breed.

Although it is one of the largest spiders in New Zealand, it has an unusual ability. It doesn’t disturb the water as it waits for its meal, and there~ is barely a ripple when it skims across the surface at lightning speed to catch its prey.

Grass water spiders deal swiftly with larger insects like damsel flies by pulling their heads under the water and holding them there until they drown.

After a meal, the grass water spider spends up to half an hour grooming itself. It wipes its eight eyes, brushes its antennae, and takes special care to clean the hairs on its body.

It is the hairs that trap tiny bubbles of air so that the spider can run down a blade of grass and stay underwater for up to an hour when it is frightened. The hairs also keep the spider dry, even underwater.

It is only when the female spider is caring for the young that she does not hunt on the water. After mating, she produces a large egg sac, which she carries around for five weeks. Once the eggs start to hatch, she attaches the sac to some blades of grass or a thistle. She then tears the sac open and releases the tiny spiders into the nursery web.

The passage tells us that the spider ().

A.feeds grass and thistles to its young

B.lives on blades of grass under the water

C.lives in the grass on the banks of streams

D.eats a meal once every five weeks

考点:教师招聘考试中学教师招聘笔试教师公开招聘考试小学英语
题型:单项选择题
磁现象可以为我们的生活提供很大的方便,以下这些做法中,不恰当的是(  )

A.将磁性材料装在冰箱的门框上,制成“门吸”

B.利用磁铁制成双面擦窗器

C.电视机上面放一块磁性治疗仪

D.用磁带来记录声音

题型:单项选择题

下列说法正确的有( )。

A.订货间隔期内的预期存货需求量变动越大,企业需要保持的保险储备量就越大

B.订货间隔期的不确定性越大,企业需要保持的保险储备量就越大

C.订货至到货间隔期的不确定性越大,企业需要保持的保险储备量就越大

D.再订货点越大,企业需要保持的保险储备量就越大

题型:单项选择题

分子为1的组合单位的符号采用什么形式?举例说明。

题型:单项选择题

首饰、长袍、腰带和靴子是蒙古族服饰的四个主要组成部分。

题型:单项选择题

下图是患甲病(显性基因为A,隐性基因为a)和乙病(为伴性遗传病,显性基因为B,隐性基因为b)两种遗传病的系谱图,据图回答:

由遗传图解可判断出甲病为常染色体上()性遗传病,其致病基因不可能在X染色体上的理由是()。

更多题库