动作电位的“全或无”特性是指同一细胞动作电位的幅度（ ）
A:
B:
C:
D:
A:
B:
C:
D:
举一反三
- 横桥的特性是（ ） A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/d9109b1706b24ebdaaa4fd2ade011f0b.png"> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/3e73caf4907c4732b31655818429fd1f.png"> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/22fe3c7df73445cdbc78681845eb442f.png"> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/dda726f3f23e497ea5706434c05ee729.png"> E: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/1e933a32e7764e73841cf6d1ad056e95.png">
- 网络函数<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/058dbbb5ab294d2980b41cd68dc78e69.png" />，其相应的单位冲激响应<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/efd689742f00449b818fd884bf9fd2cf.png" />为（ ） A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/571d5a5173d64731a7a1ed5c3ffaf403.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/b923d3ac7e9743c68ad701c170b784b4.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/d3c454406cd94e97a23806c9ba83d4e0.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/159fc59d34794c2b9f24f1ddbc368a14.png" />
- 图示单口网络相量模型的等效阻抗等于( )<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/20721ffbb1d64ad29d5b9cc9c3e8c602.png" /> A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/a505e0c3f6c540dfa69303f1383bf5d4.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/658644cc34254a9bb00700b269a6de65.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/8f656c874947474889404774e2eaf5bc.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/6438ce35699e439d800b0a42dda62d29.png" />
- 静力荷载作用下，侧焊缝的计算长度不宜大于（）。 A: 120<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/a8715ab036924c41acc716e86b83a5d7.jpg" /> B: 60<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/a8715ab036924c41acc716e86b83a5d7.jpg" /> C: 40<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/a8715ab036924c41acc716e86b83a5d7.jpg" /> D: 80<img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/a8715ab036924c41acc716e86b83a5d7.jpg" />
- 将扬氏双缝干涉实验装置放入折射率为n的介质中，其条纹间隔是空气中的 A: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/c95635ce72a849538975d8db8b46c522.png" /> B: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/f8288c3d5f1142faa90e71323aa5dc91.png" /> C: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/2987a330c95f4c86b5cb38030330a3ef.png" /> D: <img src="https://image.zhihuishu.com/zhs/onlineexam/ueditor/202003/57ebaf5744c14ffcbb710139760a6720.png" />