2.(15分,除标注外,每空2分)(1)碳源(能量)不能葡萄糖溶液的浓度过高会引起谷氨酸棒状杆菌失水,从而影响发酵过程高压蒸汽灭菌(1分)利于菌体与培养液充分接触,便于谷氨酸棒状杆菌获得营养物质和排出代面废物(2)通入无菌空气和加入缓冲液维持适宜的pH(3负)反馈既能满足微生物对物质的需求,也避物质的浪费,使生物体内的物质维持在一定的析】(1)葡萄糖可为谷氨酸棒状杆菌的生长提供碳源(能量),葡萄糖溶液的浓度过高会引起谷氨酸棒状杆菌失水,从而影响发酵过程,因此培养基中的葡萄糖溶液的浓度不能由15%左右提升到25%。培养基通常采用高压蒸汽灭菌法灭菌。由于液体培养基有利于菌体与培养液的充分接触,便于谷氨酸棒状杆菌获得营养物质和排出代谢废物,因此生产谷氨酸的过程中通常选用液体培养基。(2)溶氧不足以及pH呈酸性时,不利于谷氨酸的产生,因此可通过通人无菌空气和加入缓冲液来为谷氨酸的产生提供适宜的条件。(3谷氨酸脱氢酶能促进谷氨酸的生成,在谷氨酸的法度超过一定程度时,会抑制谷氨酸脱氢酶的活性,从而使谷氨酸维持在一定的含量,既满足微生物对物质的需求,也避免物质的浪费

NoticeMay I have your attention, please? I have anannouncement to make on behalf of our Students'Union. To arouse students' awareness of savingprecious food, our school is planning to hold a speechcontest entitled"Saving food, starting from me"in theschool hall. The exact time is scheduled at 2: 00 p.m.25th, OctoberEveryone including our teachers is welcomed totake an active part in the competition. The contents ofthe speech mainly involve in the importance of savingfood, how to save food and starting from ourselvesLooking forward to your active participationStudents'Union

以上就是2019~2022期英语周报人教版答案，更多英语周报答案请关注本网站。

本文地址： http://www.ncneedu.cn/post/5867.html

文章来源：admin

版权声明：除非特别标注，否则均为本站原创文章，转载时请以链接形式注明文章出处。