I am writing my thesis in biology, and am not sure how to format the M&M section of my thesis.
One option is like an experiment protocol, with a lot spaces, itemized lists of steps, etc...
Another option is more like an article, which is usually more dense, and harder to comprehend, but takes up less space.
Which format is the norm for a thesis?
Thesis writers generally have much more freedom to format them as they please. The only real requirement is that it follows any guidelines of the department and institution to which it is submitted, and receives the approval of the writers' thesis committees.
That said, I believe that these days, space should not really be a limiting consideration for a thesis writer. The methods section should be as long as needed to convey the necessary information. In addition, since this is not normally a journal publication, there is much more room to explain things in detail—which can be very useful for future members of the lab group who might follow up the same project.