从一个新鲜的紫色洋葱表皮细胞来看,组成原生质层的是 ①细胞壁 ②细胞膜 ③细胞质

题型:选择题

问题:

从一个新鲜的紫色洋葱表皮细胞来看,组成原生质层的是

①细胞壁 ②细胞膜 ③细胞质 ④液泡膜 ⑤液泡 ⑥细胞液[ ]

A.①②③

B.②③④

C.③④⑤

D.②④⑥

考点:细胞的吸水和失水
题型:选择题

If we are all willing to make _____ with each other ______ when we are in dispute,quarrels and conflicts will be avoided and we will surely live in peace.

A.acquaintance

B.adjustment

C.contact

D.compromise

题型:选择题

     One kind of female butterfly mates only once in its life —and then closes its wings to avoid

"harassment" when pursued by persistent and unwanted males, a Japanese researcher said.

     Observations of the Small Copper Butterfly, a colourful orange and black butterfly, showed that some

females closed their wings when males flew by, but only when they were males of their own species, said

Jun-Ya Ide, an associate professor at Kurume Institute of Technology in Fukuoka, western Japan.

     "When we looked into why, the males were courting the females. They do this very stubbornly, so the

females sometimes try to get away-or prefer to stay unobserved," he added.

     Ide and his colleagues brought a model of a male butterfly near the females to test their reactions and

found that young females that had yet to mate kept their wings open, but those that had already mated

closed them.

     Not only can the persistent attentions of unwanted suitors harm the delicate females, fleeing from them

—with the male often in pursuit —uses up strength and can even shorten their lives, he added.

     "Closing their wings makes them less visible, helping them avoid communication with their own species. We figured they were trying to avoid harassment by males," Ide said.

1. What does the word "harassment" mean in the paragraph?

A. sexual invasion  

B. embarassment  

C. attack  

D. threat

2. Why some some females closed their wings when males flew by?

A. because the female butterfly mates only once in its life.

B. because they close their wings to avoid "harassment" when pursued by persistent and unwanted

males.

C. because they don’t like the male butterfly at all.

D. because they are afraid of the male butterfly.

3. According the the passage, which is correct?

A. The females closed their wings when males flew by.

B. The female butterfly mates only once in its life.

C. Only the model of a male butterfly can make the young female butterflies to keep their wings open.

D. Not only can the persistent attentions of wanted suitors harm the delicate females, fleeing from them

—with the male often in pursuit -- uses up strength and can even shorten their lives.

题型:选择题

某商业综合体地上26层、地下3层,建设用地面积8.95万m2,总建筑面积37.73万m2,其中地上建筑面积27.08万m2、地下建筑面积10.65万m2。该建筑地上一层至三层设计为室内步行街,通过若干中庭互相连通。步行街建筑面积43411m2,其中首层建筑面积15922m2,步行街净宽11~15m。

该建筑地下室主要使用性质为汽车库、机电设备用房、物业服务用房,首层主要使用性质为百货、主力店、室内步行街和临街商铺,二、三层主要使用性质为室内步行街、百货、电玩、酒楼、歌舞厅,四至六层主要使用性质为百货、酒楼、电影院,七至二十六层主要使用性质为五星级酒店。该建筑除室内步行街的防火分区划分、安全疏散,以及部分疏散楼梯间在首层需借助室内步行街进行疏散等问题以外,其他消防设计均满足现行有关国家工程消防技术标准的规定。

在消防性能化设计评估中,通过隔离室内步行街中的商业火灾荷载,限制室内步行街内部的火灾荷载,设置有效的火灾探测、自动灭火、防排烟等消防措施,将步行街设置为“临时安全区”(也称为“准安全区”),以解决步行街防火分区面积超大、借用步行街疏散等问题。

根据以上场景,回答下列问题:

1.哪些建筑内容可以进行建筑性能化防火设计?哪些建筑不允许开展建筑性能化防火设计?

2.建筑物性能化消防设计的基本程序有哪些?

3.消防性能化设计评估针对室内步行街应采取的相应消防措施有哪些?

4.请简述针对本项目室内步行街防火分区面积扩大、借用室内步行街进行疏散的消防问题,应当采取何种消防措施解决存在的消防问题?

题型:选择题

造成文丘里洗涤器压差升高的原因有()。

A.激冷水量过大

B.洗涤器内部堵塞

C.粗煤气量过大

D.炉温过高

题型:选择题

通过文本框的( )属性可以获得当前插入点所在的位置。

A) Position
B) SelStart
C) SelLength
D) SelText

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