In science, it is especially important to write so readers can easily get the intended meaning. With non-scientific prose, an author's intended meaning may not be immediately obvious, but not getting it usually doesn't result in insurmountable confusion like it can in science.
Science can be complicated.
For clear scientific communication, it often seems necessary to present two or more ideas simultaneously. This isn't possible given the limitations of language, primarily its linearity. But authors can deal with the problem by using sentences with dependent clauses. Authors can also present more than one idea simultaneously using boxes or hyperlinked text, but readers still will encounter the material in a sequential way. Scientists who make use of the distinction between which and that benefit in three areas.