They are still far too young to cut or show anything. Growth seems rather slow for 5 weeks, how are they being lit/fed?
On my plants (Kush, Aurora Indo), they'll have 9-10 strong nodes and begin to show the pistil hairs on the females by week 5 or so. The one male I've culled so far, didn't show anything to me at all even after 7 weeks. After flowering a clone for about 2 1/2 weeks, it showed the ball sacks.
Looks like yours could use some strong blue light to get some more node action going then you'll either see the preflowers, or you can take a couple of cuttings and sex them. As the cliche goes with this hobby; Be patient, it'll happen.