Acrosome Reaction
  1. Unreacted sperm. Cannot fertilize an egg until reacted.
  2. Surface receptors on the sperm react to egg jelly causing the acrosome to fuse with the plasma membrane and start the g-actin to polymerize into f-actin |||.
  3. The process continues as the polymerizing actin pushes out from the sperm.
  4. Actin extension is complete and the bindin molecules from within the acrosome coat the surface of the sperm. Bindin will be needed later to bind with the egg surface.

Information Only: you will not be able to observe this happening yourself. This entire process takes only a few seconds to complete.