【判断题】自动扶梯的塑料橡胶车轮可使梯级运转平稳,减少噪声。
【简答题】胃底腺组成细胞有哪些?其两种主要组成细胞的结构及功能如何?
【判断题】构成胃底腺的细胞有壁细胞、主细胞、颈黏液细胞、潘氏细胞和内分泌细胞。
【简答题】构成胃底腺的细胞有()()()()()。
【简答题】胃底腺主细胞的超微结构特征是:细胞基底部及核周围有丰富的_________ 和核上方有发达的_________、游离端胞质内有大量的_________,它们都是与合成蛋白质有关的细胞器。
【多选题】电子商务企业进行定位十分必要,原因包括( )。
【单选题】听力原文: One of the reasons for our success as a species is our ability to eat and thrive on a large variety of foods. Many animal species have become extinct or are on the edge of extinction partly beca...
A.
It is all ability both man and animals possess.
B.
It is the reason for man's superiority over animals.
C.
It is one of the reasons for man's success as a species.
D.
It is a proof of our superior intelligence.