搜题请搜索小程序“爱下问搜题”
问题 单项选择题

对Km值的意义描述不正确的是

A．对于同一底物，不同的酶有不同的Km值
B．Km值与酶的结构有关
C．Km=(K2+K3)/K1
D．Km值等于反应速度为最大速度1/2时的酶浓度
E．Km值等于反应速度为最大速度1/2时的底物浓度

答案

参考答案：D

写作题

Getting up early has been regarded as a good habit since ancient times. Many years ago, people thought that if we went to bed early and got up early, we would be energetic the whole day. So, getting up early is of great importance to us all.

In fact, morning is the best time of a day. In the morning, the air is the freshest and people are usually in the best conditions. Many of us may have the experiences that we memorize some things more quickly and accurately in the morning than at any other time of the day. If we do some morning exercise or only take a short walk in the morning, we can build our bodies and become much healthier. Also we will have enough time to make a plan and get ready for our work or study of the day if we get up early. However, if we get up late, we'll probably have to do everything in a great hurry.

Let us remember getting up early is a good habit and try our best to keep it. If we stick to getting up early every day, we will certainly benefit a lot from it.

【写作内容】

(1)以约30个词概括短文的要点：

(2)然后以约120个词就“早起还是晚起好”这个主题发表你的看法，并包括以下要点：

①你是喜欢早起还是晚起；

②结合自己学习或生活的例子，说明你喜欢这样做的理；

③你的父母或教师有何建议；

④你如何看待他们的建议?

【写作要求】   

(1) 可以使用实例或其它论述方法支持你的论点，也可以参照阅读材料的内容，但不得直接引用原文中的句子；

(2) 标题自拟。

【评分标准】

概括准确、语言规范、内容合适、篇章连贯。
查看答案
填空题

倒锤线设备由（），（），（），（）和观测平台组成。
查看答案