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Fig. 1. An individualizing cyst. Individualization takes place at the cystic bulge.
The membrane reorganization occurs as the actin cone (red triangle) moves down
along the sperm axoneme from its head to the end of the tail. Arrow indicates
the direction of movement. Cytoplasm and membranous organelles are squeezed
out and accumulate in the cystic bulge as the actin cones move down the cyst.
At the end of individualization all cytoplasm and organelles are discarded as
a waste bag and 64 thin individual sperm are formed.