Fig. 7. Backward forces were sufficiently strong to achieve the backward movement of an entire acentric half-bivalent. (A-E) Selected frames from a time-lapse recording of an operation in which the kinetochores were removed from a segregating half-bivalent. Here the acentric arms remained `stuck' together following the operation and moved backward as a unit, in this case with an initial velocity of 2 µm/minute. (A) Before the operation. (B) After the operation, the removal of kinetochores is evident from the truncated appearance of the half-bivalent; the operation also generated a ribbon of denatured nucleoprotein, called a sniglet (arrowhead). (C) The sniglet (arrowhead) was transported polewards, but the truncated half-bivalent moved backwards towards its partner. (D) The acentric arms continued moving towards the partner's pole, as the sniglet (arrowhead) was transported further polewards. (E) At late anaphase, the truncated half-bivalent was located in the opposite half-spindle and the sniglet (arrowhead) was located near the spindle pole. Times are given in minutes and seconds. Bar, 5 µm (E).

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