The main verb or the predicate of that sentence is may play.
So notice we don't get to the main verb for a long time.
We have molecular species and then this long descriptive clause, and
then we finally get to the main verb at may play.
The problem is that the reader is waiting for the verb.
Until you give the reader the verb,
the reader doesn't know where you're going with the sentence.
So putting too much distance between the subject of the sentence and
the main verb is a problem.
That's another thing that we'll talk about in great detail next week
in our unit on verbs.
So I took that passage and I rewrote it to try to fix some of these issues.
I did not have the authors sitting right next to me while I was doing this edit, so
I am not 100% sure that this is what they were trying to say,
but I think I got the gist of it.