简述植物激素的主要特点？

简述裸子植物与被子植物的主要区别。

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

简述异花授粉园艺植物的遗传特点？

根据菌根真菌本身的特征及其与不同植物形成菌根的形态结构，可将菌根划分为（）菌根、（）菌根和（）菌根3种主要类型。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

简述农学（广义、中义、狭义）的含义。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。