When released into the atmosphere, the refrigerant Freon damages the Earth’s ozone layer. A new kind of refrigerant does not have this effect. The manufacturer claims that replacing Freon with the new refrigerant in both new and existing refrigerators will prevent any further Freon damage to the ozone layer apart from that being done by the Freon already in the atmosphere.
Which of the following must be true if the manufacturer’s prediction is to prove accurate

A．Freon can be replaced with the new refrigerant without releasing any Freon into the atmosphere.

B．The damage already done to the ozone layer is not of environmentally significant proportions.

C．The atmosphere can reverse the damage to the ozone layer caused by the past use of Freon.

D．The new refrigerant can counteract the damaging effects of Freon on the Earth’s atmosphere.

E．(E) The new refrigerant causes no environmental damage of any kind when it is released into the atmosphere.

下列关于兴奋在突触传递过程的叙述，错误的是（）。

A.一般包括电-化学-电3个环节

B.不需要Ca²⁺参与

C.突触小泡释放递质

D.突触后膜上存在特异性受体

E.突触后膜可发生去极化或超极化