Well, I have two thoughts:
more explicit effort to answer your own question needed.
We ask that all question posters here attempt to search for an answer to their own question and explicitly indicate what research they've already done, what they learned, and what is still confusing or unknown to them. Our goal is not to simply be an answer site, but rather a site that promotes self-learning with some expert help along the way.
Downvotes from close voters?
You also have 2 close votes for being "opinion-based" (opinion-based questions are off topic on BIO.SE). I'm not sure if these coincide with your downvotes or not. Regardless, I personally don't believe your question is asking for an answer that is necessarily (or even likely) opinion-based, so I think such close votes might be a bit off base.
I think both reasons are going on here. You can't do anything about the latter, though perhaps you could adjust your wording in some way to convince others that you're looking for a technical term vs an opinion to avoid further close votes. But I would definitely recommend that you provide more explicit evidence that you tried answering this question on your own (either through linking to other sources, citing information, or simply detailing where you've already looked and what that search turned up).
Hope this helps!