【简答题】如图是人体内气体交换和运输的示意图,请据图回答下列问题. (1)图中A、B、C、D分别代表的是什么物质? A是______,B是______,C是______,D是______. (2)组织细胞利用D通过______作用分解有机物释放______的同时也产生了C. (3)A和B的交换过程是通过______(填下列过程前的字母)实现的. A.呼吸作用 B.呼吸运动 C.气体扩散 ...
【单选题】Greece, economically, is in the black. With very little to export other than such farm products as tobacco, cotton and fruit, the country earns enough from. invisible earnings' to pay for its needed, ...
A.
Greek income and expenditures
B.
The improving economic situation in Greece
【简答题】Dickson Despommier is a public health professor at Columbia University in New York City. His area is environmental health sciences. One day nine years ago, he and his students developed an idea. They ...
【简答题】This farm is growing organic vegetables for more than ten years now.
【简答题】Greece, economically, is in the black. With very little to export other than such farm products as tobacco, cotton and fruit, the country earns enough from ' invisible earnings' to pay for its needed,...
【多选题】竞争者存在调研主要针对以下 ( )方面进行调研。
【单选题】转基因作物同普通植物的区别只是多了能使它产生额外特性的基因。早在1983年,生物学家就已经知道怎样通过生物工程技术将外来基因移植到某种植物的脱氧核糖核酸中去,以便使它产生靠杂交方式根本无法获得的某种新特性:抗除莠剂的特性、抗植物病毒的特性、抗某种害虫的特性等。用以移植的基因可来咱任何生命体:细菌、病毒、昆虫等。 下列对“转基因作物”这一概念的理解,正确的一项是( )。
A.
因环境影响脱氧核糖核酸的变化而产生额外特性的作物
B.
能够产生抗除莠剂、抗植物病毒等额外基因的作物
C.
一种利用移植其他生命体基因而形成的新的杂交作物
【单选题】By referring to photos of people queuing up and poultry farm medicine, the author intends to show______.
A.
any announcement from medical research institutions is strongly believed
B.
doubts about the drug s potency against the coronavirus are growing
C.
the herbal flu medicine is still in the early stages of research
D.
the behavior that people rush to buy this medicine like crazy is very irrational