试述动作电位产生的机制。 -题库考试答案搜索网

试述动作电位产生的机制。

问答题

2022-04-02 14:56

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正确答案

动作电位的产生机制:细胞受刺激→膜上少量电压门控Na⁺通道开放(激活)→Na⁺顺电-化学梯度→少量Na⁺内流→膜去极化到某一电位水平(阈电位)→大量Na⁺通道开放→大量Na⁺内流→形成AP上升支(去极相)→达到Na⁺平衡电位,膜电位内正外负(动力:电位差和浓度差;阻力:电位差)→Na⁺通道失活→膜上K⁺通道开放→膜内K⁺顺电-化学梯度向外扩散→膜内电位变负→AP下降支(复极相)→K⁺平衡电位→Na⁺通道恢复(复活)。恢复到静息电位前的后电位还有钠泵的参与。

试题解析

标签：黑龙江省教育学院体育教育（函授）专升本人体生理学平时作业2

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