No, jurors are not allowed to ask questions. Like I said, it wasn't the lynchpin in the case(deliberations were decidedly short). It was useful to add to a much more extensive list (even more extensive than I included). That's why I don't particularly like the expert witness system the US has, like I said.

Edit: and to clarify the reasoning for the test, the defendant said he had sex with the victim several days before. The background of the test was to show there was no biological breakdown to suggest that. My memory isn't perfect on it since it was several years ago.

Here's a link to the case that gives a good overview, but realize that it doesn't have ALL the evidence we reviewed. https://www.fredericknewspost.com/news/crime_and_justice/courts/man-convicted-in-1996-rape-and-murder-of-frederick-girl/article_a71161c5-f52a-5d1c-844d-0e88e3f9cae8.html