Channel mediated diffusion N N店 Na]o>Na力]i 膜外 膜肉 K]>K]。 转运的物质：各种带电离子 characteristic ①selectivity ,选择性 ②high velocity高速率 3The channel can opened or closed by gate[K 转运的物质:各种带电离子 +] i ＞[K+]o [Na+]o ＞[Na+] i Channel mediated diffusion characteristic ①selectivity 选择性 ②high velocity 高速率 ③The channel can opened or closed by gate