No, you just take your passport and the print-out of the biometrics appointment confirmation (I think it also says to take the printed application too, but I don't think you need it).
They will check your ID, stamp the confirmation sheet, take your fingerprints and photo and then you leave... shouldn't take more than 5-10 minutes in total.
The biometrics are done by US immigration on behalf of UKVI. They don't know anything about your visa application or how you apply or what documents you are supposed to have - they just take your photo and fingerprints and send you home. Then they transmit the biometrics to Sheffield electronically, ready to be linked to your documents when they arrive.