Tracing the history of the conch throughout the novel, explain how it is used, its purpose, its meaning to the boys, and what becomes of it?Refer...

This question requires an essay-length response.  Here are
some ideas to help you get started:

As the novel opens,
readers learn that the boys' plane has crashed on an uninhabited island.  As the
children begin to gather on the beach to try to figure out what happened (and what they
should do next), Piggy suggests that Ralph blow the conch as a signal for everyone to
come together for a meeting.  Eventually, the boys learn to associate the sound of the
conch with a summons, and understand that they must come to order when the shell is
blown.  Thus, the conch shell comes to symbolize order in the novel, and whoever has the
conch has the right to speak. 

As chaos begins to take over
on the island, the conch becomes less effective; the boys start to ignore its sound, and
Ralph becomes frustrated when he realizes that he's losing control.  Ultimately, in the
altercation that results in Piggy's death, the conch is shattered; this act symbolizes
the complete loss of order on the island. 

Again, you've
asked a very complex question--one that requires an answer that is too in-depth to be
posted here.  I hope this helps you get started.  Good luck!