搜题请搜索小程序“爱下问搜题”
问题 单项选择题

细胞膜能被脂质溶剂和蛋白酶处理后溶解，由此推断细胞膜的化学成分主要是（）

A.磷脂和多糖

B.磷脂和蛋白质

C.蛋白质和核酸

D.蛋白质和多糖

答案

参考答案：B

解析：

根据相似相容原理和酶的专一性，可知细胞膜的化学成分是脂质和蛋白质，故B正确。

考点：本题主要考查细胞膜的结构，意在考查考生能理解所学知识的要点，把握知识间的内在联系，形成知识的网络结构的能力。

单项选择题

建设用地使用权人是否有权对土地进行抵押( )。

A．在任何情况下都无权

B．有权，但法律另有规定的除外

C．在任何情况下都有权

D．有权，但是需要行政主管部门的同意
查看答案
单项选择题

Deflation is an economic theory relating changes in the price levels to changes in the quantity of money. In its developed (1) , it constitutes an analysis of the (2) underlying inflation and deflation. As (3) by the English philosopher John Locke in the 17th century, the Scottish (4) David Hume in the 18th century, and (5) , it was a weapon (6) the mercantilists, who were thought to equate wealth with money. If the (7) of money by a nation merely raised (8) , argued the quantity theorists, then a "favourable" balance of trade, (9) desired by mercantilists, would increase the supply of money but would not in-crease (10) . In the 19th century the quantity theory (11) to the ascendancy of free trade over protectionism. In the 19th and 20th centuries it played a part in the (12) of business cycles and in the theory of foreign (13) rates.

The (14) theory came under attack during the 1930s, (15) monetary expansion seemed ineffective in combating deflation. Economists argued that the levels of investment and government spending were more important than the money supply in determining economic activity.

The tide of opinion (16) again in the 1960s, when experience (17) post-World WarⅡ inflation and new empirical (18) of money and prices— (19) A Monetary History of the United States (1963) by Milton Friedman and Anna Schwartz—restored much of the quantity theory’ s lost prestige. One implication of this theory is that the size of the stock of money must be considered when shaping governmental policies (20) to control prices and maintain full employment.

15（）

A.where

B.what

C.when

D.which
查看答案