How did humans understanding of microbes and their relationship with disease shift over time?

Essay must be based on chapters 1 & 3. Here are your two questions that must be answered. I will upload the textbook!1. How did humans understanding of microbes and their relationship with disease shift over time? (In other words, what did they think about microbes hundreds or thousands of years ago versus now?) What are three contributors/experiments/events that shifted our understanding of this topic?2. 3. If you were going to create a timeline of important experiments or discoveries that shaped our current understanding of microbiology, and you could only choose three, which three would you choose? Name and describe them. Why did you choose these three over any others?• You should use your textbook and at least two additional scholarly sources for each question. For a source to be considered scholarly, it should be a textbook or journal article or come from a url that ends in .gov, .edu, or .org. It is important to me to hear your understanding of topics. Do not use quotes from other sources. Instead, rephrase to put all ideas into your own words (please remember you still need to cite information that you rephrase).• use at least two scholarly sources in addition to the textbook for each question. Sources should be cited in-text and full citations provided in a list at the end or on a separate page. Citations can be MLA