皮皮学，免费搜题
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【单选题】
可用于分离螺甾烷甾体皂苷和呋甾烷皂苷的方法是
A.
乙醇沉淀法
B.
pH 梯度萃取法
C.
醋酸铅沉淀法
D.
胆甾醇沉淀法
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举一反三
【单选题】下列不属于排泄的是
A.
消化道排出食物残渣
B.
肾脏排出尿液
C.
肺呼出CO2
D.
皮肤分泌汗液
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【单选题】Almost all cell phones sold in Canada are sold at subsidized prices, with expensive plans. Almost all cell phones sold in Europe are sold at full price with cheaper plans. A cell phone manufacturer kn...
A.
geographic
B.
economic
C.
demographic
D.
benefit
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【单选题】Cell phones are now widely used,  _______possible for us to talk to anyone from almost anywhere.
A.
make it
B.
to make it
C.
making
D.
making it
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【简答题】New York State has passed the USA’s first state law banning motorists talking on hand-held cell phones. The ban will begin November 1, although drivers caught using hand-held cell phones will be given...
查看完整题目与答案
【多选题】下列第一类防雷建筑物防闪电电涌侵入的措施正确的是：（）。
A.
室外低压配电线路应采用电缆直接埋地敷设
B.
在入户处应将电缆的金属外皮、钢管接到等电位连接带或防闪电感应的接地装置上
C.
当全线采用电缆有困难时，可采用架空线路，架空线与建筑物的距离不应小于5m
D.
采用架空线路时，在电缆与架空线路的连接处，尚应装设户外型电涌保护器
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【单选题】下列不属于排泄的是（　　）
A.
排便
B.
排尿
C.
呼气
D.
排汗
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【简答题】Smoking was banned on almost all ______ in 198
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【单选题】Driving while talking on a cell phone is almost as dangerous as driving after drinking.
A.
Y
B.
N
C.
NG
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【单选题】下列不属于排泄的是
A.
出汗
B.
排尿
C.
呼出二氧化碳
D.
排便
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【多选题】In almost all adult tissues, cells are continually dying and being replaced; throughout this hurly-burly of cell replacement and tissue renewal, the organization of the tissue must be preserved due to...
A.
Cell communication: each type of specialized cell continually monitors its environment for signals from other cells and adjusts its behavior accordingly; the proliferation and even the survival of most vertebrate cells depends on such social signals. This communication ensures that new cells are produced and survive only when and where they are required.
B.
Selective cell adhesion: because different cell types have different cadherins and other cell adhesion molecules in their plasma membrane, they tend to stick selectively, by homophilic binding, to other cells of the same type. They may also form selective attachments to certain other cell types and to specific extracellular matrix components. The selectivity of these cell adhesions keeps cells in their proper positions.
C.
Cell memory: specialized patterns of gene expression, evoked by signals that acted during embryonic development, are afterward stably maintained, so that cells autonomously preserve their distinctive character and pass it on to their progeny. A fibroblast divides to produce more fibroblasts, an endothelial cell divides to produce more endothelial cells, and so on.
D.
all the above.
查看完整题目与答案
相关题目：
【单选题】下列不属于排泄的是
A.
消化道排出食物残渣
B.
肾脏排出尿液
C.
肺呼出CO2
D.
皮肤分泌汗液
查看完整题目与答案
【单选题】Almost all cell phones sold in Canada are sold at subsidized prices, with expensive plans. Almost all cell phones sold in Europe are sold at full price with cheaper plans. A cell phone manufacturer kn...
A.
geographic
B.
economic
C.
demographic
D.
benefit
查看完整题目与答案
【单选题】Cell phones are now widely used,  _______possible for us to talk to anyone from almost anywhere.
A.
make it
B.
to make it
C.
making
D.
making it
查看完整题目与答案
【简答题】New York State has passed the USA’s first state law banning motorists talking on hand-held cell phones. The ban will begin November 1, although drivers caught using hand-held cell phones will be given...
查看完整题目与答案
【多选题】下列第一类防雷建筑物防闪电电涌侵入的措施正确的是：（）。
A.
室外低压配电线路应采用电缆直接埋地敷设
B.
在入户处应将电缆的金属外皮、钢管接到等电位连接带或防闪电感应的接地装置上
C.
当全线采用电缆有困难时，可采用架空线路，架空线与建筑物的距离不应小于5m
D.
采用架空线路时，在电缆与架空线路的连接处，尚应装设户外型电涌保护器
查看完整题目与答案
【单选题】下列不属于排泄的是（　　）
A.
排便
B.
排尿
C.
呼气
D.
排汗
查看完整题目与答案
【简答题】Smoking was banned on almost all ______ in 198
查看完整题目与答案
【单选题】Driving while talking on a cell phone is almost as dangerous as driving after drinking.
A.
Y
B.
N
C.
NG
查看完整题目与答案
【单选题】下列不属于排泄的是
A.
出汗
B.
排尿
C.
呼出二氧化碳
D.
排便
查看完整题目与答案
【多选题】In almost all adult tissues, cells are continually dying and being replaced; throughout this hurly-burly of cell replacement and tissue renewal, the organization of the tissue must be preserved due to...
A.
Cell communication: each type of specialized cell continually monitors its environment for signals from other cells and adjusts its behavior accordingly; the proliferation and even the survival of most vertebrate cells depends on such social signals. This communication ensures that new cells are produced and survive only when and where they are required.
B.
Selective cell adhesion: because different cell types have different cadherins and other cell adhesion molecules in their plasma membrane, they tend to stick selectively, by homophilic binding, to other cells of the same type. They may also form selective attachments to certain other cell types and to specific extracellular matrix components. The selectivity of these cell adhesions keeps cells in their proper positions.
C.
Cell memory: specialized patterns of gene expression, evoked by signals that acted during embryonic development, are afterward stably maintained, so that cells autonomously preserve their distinctive character and pass it on to their progeny. A fibroblast divides to produce more fibroblasts, an endothelial cell divides to produce more endothelial cells, and so on.
D.
all the above.
查看完整题目与答案