The Genesis Chamber was a Kryptonian birthing facility that contained the fetuses of Krypton's future population. A miniaturized Genesis Chamber was also onboard the Fortress of Solitude on Earth until it was destroyed during the Battle of Metropolis.
The Genesis Chamber was fashioned on the planet Krypton to house the Growth Codex and all unborn Kryptonian gene seeds that would occupy prospective Kryptonian generations. Aquabots were utilized to control and preserve the Genesis Chamber so that no Kryptonian would ever enter or interfere with the birthing procedure. Thousands of copies were created and stored aboard Scout Ships that were sent across the galaxy to colonial outposts, starting new Kryptonian worlds.
During the Kryptonian Civil War, General Zod initiated a coup d’état to take over Krypton after his discontent at the fashion that Krypton was being run to the edge of annihilation. Scientist Jor-El absconded his custody and flew to the Chamber, then he swam to the bottom to retrieve the Codex to stop Zod from using it by embedding it in the cells of his infant son Kal-El.
A Chamber survived aboard the Fortress of Solitude on Earth. Jor-El showed this to his son and told him of its purpose. Upon arriving on the planet, General Zod planned to use the Genesis Chamber housed in a lost scout ship to help his plan to recreate Krypton on Earth. The Genesis Chamber was later destroyed by Superman when he brought the ship down. Despite its apparent destruction, Lex Luthor later used the remains of the Genesis Chamber to metamorphose the body of Zod, combined with his own blood, to create the deformed monster Doomsday to kill Superman.