Asmachta is no longer part of the Beraisa, but rather an answer to the original question of the Gemara. The Gemara wrote above that one is not Chayav for Toldos other than Zeri'ah and Betzirah. On this the Gemara cited the Beraisa which lists other Toldos and says that one is Chayav for them from the Pasuk of ??? ?? ("Sadecha Lo"). From the word "Yachol" and on is merely the end of the Beraisa which lists Toldos for which one is not Chayav, while the question is from the beginning of the Beraisa which lists the Toldos for which one is Chayav. To this the Gemara answers that the Toldos in the Beraisa are only Asur mid'Rabanan and the Pasuk is an Asmachta.

D. Zupnik