Fig. 3. The movement of an acentric fragment generated by cutting a trailing arm from a segregating half-bivalent conformed to one of three types. (A-C) The single trailing arm that was to be severed is represented by an open rectangle and the acentric fragment generated by cutting is represented by an open square. The kinetochore-containing fragment is represented by an open square connected to a circle, the latter representing the centromere/kinetochore domain of the half-bivalent. For simplicity, only the to-be-cut arm and its partner are included. (A) Type 1 fragment: the fragment moved rapidly backwards across the equator into the opposite half spindle (A2) to make contact with its partner (A3) and then moved along with its partner to the lower pole (A4). The tethered arm of the partner half-bivalent is shown with a solid rectangle and solid circle. (B) Type 2 fragment: the fragment moved backwards across the spindle into the opposite half spindle (B2), but it did not make contact with its partner (B3) as in (A). Further movement of the fragment to the opposite pole occurs after the partner (solid) reaches the pole (B4). (C) Type 3 fragment: this fragment moved backwards a short distance (or did not move backwards at all) without crossing the equator (C2) then shifted from backward movement to movement to the correct pole (C3) and at late anaphase it was located near its original pole (C4).

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