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【单选题】
离心泵的工作点是指A.
与泵最高效率是对应的点
B.
由泵的特性曲线所决定的点
C.
由管路特性所决定的点
D.
泵的特性曲线与管路特性的交点
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【判断题】Subrogation Principal states that in the event of loss of or damage to the subject matter insured resulting from an insured peril, the insured is placed in the same position that he enjoyed immediatel...
A.
正确
B.
错误
【单选题】If the goods in question are covered by an insurance company, the ( ) may obtain a letter of subrogation from the consignee after his payment of indemnity to the consignee.
A.
supervision
B.
look
C.
insurer
D.
feel
【单选题】徐志摩的诗歌创作只有短短十年,留下了《志摩的诗》等四本诗集,其中诗人因飞机失事身亡后出版的是( )。 A. 《志摩的诗》 B. 《翡冷翠的一夜》 C . 《猛虎集》 D .《云游集》
A.
《志摩的诗》
B.
《翡冷翠的一夜》
C.
C ． 《猛虎集》
D.
D ．《云游集》
【多选题】How do plant cells differ from animal cells in making use of receptors and signaling strategies?
A.
Like animals, plants make extensive use of transmembrane cell-surface receptors—especially enzyme-coupled receptors to recognize the extracellular signal molecules that control their growth and development. The spindly weed Arabidopsis thaliana has hundreds of genes encoding receptor serine/threonine kinases.
B.
These are, however, structurally distinct from the receptor serine/threonine kinases found in animal cells .
C.
The plant receptors are thought to play an important part in a large variety of cell signaling processes, including those governing plant growth, development, and disease resistance.
D.
In contrast to animal cells, plant cells seem not to use RTKs, steroid-hormone-type nuclear receptors, or cyclic AMP, and they seem to use few GPCRs.
【多选题】The plant cells share several pathways of carbohydrate metabolism with animal cells:
A.
The plant cell carries out the same processes that generate energy in animal cells (glycolysis, citric acid cycle, and oxidative phosphorylation).
B.
It can generate hexoses from three- or fourcarbon compounds by gluconeogenesis.
C.
It can oxidize hexose phosphates to pentose phosphates with the generation of NADPH (the oxidative pentose phosphate pathway).
D.
I t can produce a polymer of (α1→4)-linked glucose (starch) and degrade it to generate hexoses.
【单选题】Plant cells have only one class of intercellular junctions——( ).
A.
tight junction
B.
plasmodesmata
C.
gap junction
D.
anchoring junction
【判断题】Subrogation Principle states that in the event of loss of or damage to the subject matter insured resulting from an insured peril, the insured is placed in the same position that he enjoyed immediatel...
A.
正确
B.
错误
【多选题】How does cytokinesis in plant cells involve the formation of a new cell wall?
A.
The mechanism of cytokinesis in higher plants is entirely different from that in animal cells, presumably because plant cells are surrounded by a tough cell wall. The two daughter cells are separated not by the action of a contractile ring at the cell surface but instead by the construction of a new wall that forms inside the dividing cell.
B.
The positioning of this new wall precisely determines the position of the two daughter cells relative to neighboring cells. Thus, the planes of cell division, together with cell enlargement, determine the final form of the plant.
C.
The new cell wall starts to assemble in the cytoplasm between the two sets of segregated chromosomes at the start of telophase. The assembly process is guided by a structure called the phragmoplast, which is formed by the remains of the interpolar microtubules at the equator of the old mitotic spindle.
D.
Small membrane-enclosed vesicles, largely derived from the Golgi apparatus and filled with polysaccharides and glycoproteins required for the cell wall matrix, are transported along the microtubules to the phragmoplast. Here, they fuse to form a disclike, membrane-enclosed structure, which expands outward by further vesicle fusion until it reaches the plasma membrane and original cell wall, thereby dividing the cell in two. Later, cellulose microfibrils are laid down within the matrix to complete the construction of the new cell wall.
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