2022年版英语周报答案42期

19.【答案】（除标明外，每空1分）(1)静息钾离子外流不需要(2)钠离子内流(2分)离体神经纤维所处环境中的钠离子浓度较低（合理即可，2分)神经元B为突触后神经元或神经元B是抑制性神经元(合理即可，2分)【关键能力】理解能力、分析能力【解题思路】(1)电极A置于细胞膜外，电极B置于细胞膜内，神经纤维没有受刺激，此时测定的是静息电位：静息电位是由钾离子外流导致的，钾离子通过离子通道从高浓度流向低浓度属于协助扩散，不需要消耗能量。(2)图2中b段电位变化是动作电位的产生过程，是由钠离子内流导致的。图2中b点表示动作电位，该神经纤维处于离体状态时，外界溶液中的钠离子浓度可改变动作电位值。兴奋在突触处只能由突触前膜传向突触后膜，刺激突触后神经元不能使突触前神经元产生兴奋；抑制性神经元释放的神经递质可抑制下一个神经元的兴奋。

第二节书面表达【写作思路】根据试题要求,考生需要写一篇记叙文,记述身边一位值得尊敬和爱戴的人。首先考生需要介绍自己最尊敬和爱戴的人是谁,简单地介绍一下他(她)。然后,陈述为什么他(她)值得尊敬和爱戴。最后,可以对前文进行一个总结,使文章结构严谨。本文的写作重点在"尊敬和爱戴的原因",考生可围绕这个要点适当拓展,从性格特点、处事风格等方面展开写作。【范文赏读】The most beloved and respected person around me is my teacher, Ms LiThough she has been teaching English for twenty years, she is still passionateabout teaching. She is kind and considerate towards us just like our dear motherWe all respect her because she always tries new ways to make her classes livelyand interesting. Hardworking and knowledgeable, she is one of the best teachersin our school. When we have a problem, we will turn to her for help. She alwaystalks to us patiently and helps us to find a solution. In our eyes, she is not onlyour teacher, but also our best friend. Those are why she deserves our respect【亮点词句】亮点词汇: beloved, respected, be passionate about, be consideratetowards, turn to sb. for help, in one's eyes亮点句式:Why引导的表语从句( why she deserves our respect)

以上就是2022年版英语周报答案42期，更多英语周报答案请关注本网站。